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3                                                                                             About this book
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                                                                                                                                                                             EXAMPLE 3
                                                                                                                                                                                         Divide 3x2 + 5 by x2 + 1
without the prior permission in writing of Oxford University Press,
or as expressly permitted by law, or under terms agreed with the appropriate                to develop. These are shown in boxes and include prompts to guide you                        ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••




                                                                                                                                                                                         Rewrite the numerator to involve a multiple of the denominator:
reprographics rights organization. Enquiries concerning reproduction
outside the scope of the above should be sent to the Rights Department,
                                                                                            through the solutions.                                                                                     3x 2 + 5 = 3(x 2 + 1) + 2
                                                                                                                                                                                                        x2 + 1        x2 + 1
Oxford University Press, at the address above                                                                                                                                            Divide each term in the numerator:

                                                                                                                                                                                                                                         =3+                           2
You must not circulate this book in any other binding or cover                               Derivations and additional information are shown in a panel.                                                                                                            x2 + 1
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                                                                                            Each section includes an exercise with progressive questions, starting
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Acknowledgements
                                                                                            ‘stretch and challenge’ questions marked with a stretch symbol
The Publisher would like to thank the following for permission to reproduce                 and investigations to apply your knowledge in a variety of situations.                  INVESTIGATION
photographs:                                                                                                                                                                        10 Use computer software or a graphical calculator to check
P38 PA Archive/PA Photos; p74 Daniel Padavona/Shutterstock; p90                                                                                                                        some of your answers to the questions in this exercise.
studiovanpascal/iStockphoto; p120 Image Source/Corbis; p138 evirgen/iStockphoto;            At the end of each chapter there is a ‘Review’ section which includes                      You may have to use abs (absolute value) button to
                                                                                                                                                                                       input a modulus.
p158 servifoto/iStockphoto; p178 Sylvanie Thomas/Shutterstock; p192 Dijital
Film/iStockphoto; p206 Jenny Horne/Shutterstock; p212 Toni Räsänen/Dreamstime;
                                                                                            exam style questions as well as past exam paper questions. There are also
p260 pixonaut/iStockphoto; p267 Lawrence Freytag/iStockphoto; p274 Dmitry                   two ‘Revision’ sections per unit which contain questions spanning a
Nikolaev/Shutterstock; p296 Hal Bergman/iStockphoto.
                                                                                            range of topics to give you plenty of realistic exam practice.
The cover photograph is reproduced courtesy of Frans Lemmens/Photodisc/Getty                The final page of each chapter gives a summary of the key points, fully
                                                                                            cross-referenced to aid revision. Also, a ‘Links’ feature provides an
The publishers would also like to thank Kathleen Austin, Judy Sadler and Charlie Bond for
their expert help in compiling this book.
                                                                                            engaging insight into how the mathematics you are studying is relevant
                                                                                            to real life.
                                                                                            At the end of the book you will find full solutions and an index.
                                                                                            The free CD-ROM contains a key word glossary and a list of essential
                                                                                            formulae as well as additional study and revision materials and the
                                                                                            student book pages.
Contents                                                                                      C4

                                                                                                  6      Partial fractions             147–158      10.8 Integration by parts                  240
C3                                                                                                6.1    Separating fractions              148      10.9 A systematic approach
                                                                                                  6.2    More partial fractions            152            to integration                       246
1     Algebra and                              3     Exponentials and                                    Review 6                          156      10.10 Volumes of revolution                248
      functions                        1–38          logarithms                           79–90          Exit 6                            158            Review 10                            256
1.1   Combining algebraic fractions       2    3.1   The exponential function, e  x
                                                                                             80
                                                                                                                                                          Exit 10                              260
1.2   Algebraic division                  4    3.2   The logarithmic function, ln x          84   7      Parametric
1.3   Mappings and functions              8    3.3   Equations involving e x and ln x        86          equations                     159–178      11     Differential
1.4   Inverse functions                  16          Review 3                                88   7.1    Parametric equations and                          equations                      261–274
1.5   The modulus function               22          Exit 3                                  90          curve sketching                     160    11.1 First-order differential equations   262
1.6   Solving modulus equations                                                                   7.2    Points of intersection              166    11.2 Applications of differential
      and inequalities                   26    4     Differentiation                     91–120   7.3    Differentiation                     168         equations                            268
1.7   Transformations of graphs                4.1   Trigonometric functions                 92   7.4    Integration                         172         Review 11                            272
      of functions                       28    4.2   The exponential function, e x           98          Review 7                            176         Exit 11                              274
      Review 1                           34    4.3   The logarithmic function, ln x         102          Exit 7                              178
      Exit 1                             38    4.4   The product rule                       104
                                                                                                                                                    12     Vectors                        275–296
                                               4.5   The quotient rule                      106   8      The binomial series 179–192                12.1   Basic definitions and notations    276
2     Trigonometry                     39–74   4.6   The chain rule                         110   8.1    The binomial series                 180    12.2   Applications in geometry           282
2.1   Reciprocal trigonometric functions  40   4.7   Further applications                   114   8.2    Using partial fractions             184    12.3   The scalar (dot) product           286
2.2   Trigonometric equations                        Review 4                               118   8.3    Approximations                      186    12.4   The vector equation of a
      and identities                      46         Exit 4                                 120          Review 8                            190           straight line                      290
2.3   Inverse trigonometric functions     50                                                             Exit 8                              192           Review 12                          294
2.4   Compound angle formulae             54   5     Numerical methods 121–138                                                                             Exit 12                            296
2.5   Double angle and half angle              5.1   Graphical methods                      122   9      Differentiation                  193–212
      formulae                            60   5.2   Iterative methods                      130   9.1    Differentiating implicit functions   194   Revision 4                             297–306
2.6   The equivalent forms for                       Review 5                               136   9.2    Differentiating parametric functions 198
      a cos + b sin                       66         Exit 5                                 138   9.3    Growth and decay                     200   Answers                                    307
      Review 2                            70                                                      9.4    Rates of change                      206   Index                                      345
      Exit 2                              74   Revision 2                               139–146          Review 9                             210
                                                                                                         Exit 9                               212
                                                                                                                                                         CD-ROM
Revision 1                            75–78
                                                                                                  Revision 3                           213–216             The factor formulae                 1–3
                                                                                                                                                           Formulae to learn
                                                                                                  10     Integration                    217–260            Formulae given in examination
                                                                                                  10.1 The trapezium rule                   218            Glossary
                                                                                                  10.2 Integration as summation             222            C3 Practice paper
                                                                                                  10.3 Integration using standard forms     224            C4 Practice paper
                                                                                                  10.4 Further use of standard forms        226
                                                                                                  10.5 Integration by substitution          228
                                                                                                  10.6 Integration using trigonometric
                                                                                                       identities                           232
                                                                                                  10.7 Integration using partial fractions 238
1
  Algebra and functions
   This chapter will show you how to
     combine algebraic fractions
     understand that some mappings are also functions
     find and use composite functions and inverse functions
     use the modulus function and sketch graphs involving it
     transform graphs of functions using translations, reflections,
     stretches and combinations of these.




Before you start
You should know how to:                                  Check in:
1 Combine numerical fractions.                           1 Calculate

   e.g. Calculate 3 + 1 = 9 + 2 = 11                        a 3+2




                                                                                                               C3
                  4 6 12 12            12                      8   3
                  3 1  3   1
                   × =   =
                  4 6 24 8                                  b 3×2
                                                               8   3

2 Find important facts to help you sketch                2 Sketch the graphs of
  graphs of functions.                                      a y = x(x - 2)
   e.g. The graph of f(x) = 1 passes through the
                            x−2                             b y = x2 + x - 2
         ( )
   point 0, − 1 , has a vertical asymptote, x = 2, and
               2                                            c y = 1 +2
                                                                    x
   approaches the value 0 as x ® ± ¥


3 Translate, reflect and stretch the graph               3 Write the equation of the image of the
  of y = f(x)                                              graph of y = f(x) when
   e.g. When the graph of y = x2 is translated              a f(x) = x2 is reflected in the x-axis
   +2 units parallel to the x-axis, its equation
                                                            b f(x) = x2 - 5x is reflected in the y-axis
   becomes y = (x - 2)2
                                                                                             ⎛ −5 ⎞
                                                            c f(x) = x2 + x is translated by ⎜    ⎟
                                                                                             ⎝ 0⎠
                                                            d f(x) = x2 is stretched with scale factor 4
                                                            parallel to the y-axis.




                                                                                                           1
1 Algebra and functions

                                                                                                                                                                                                                                                                                                                                                                      Dividing by a fraction is equivalent to multiplying by its reciprocal.
           1.1                             Combining algebraic fractions




                                                                                                                                                                                                                                                                                                                                                          EXAMPLE 3
                                                                                                                                                                                                                                                                                                                                                                                                                           x 2 − 2x ÷ x 2 − 4
                     Addition and subtraction                                                                                                                                                                                                                                                                                                                           Simplify
                                                                                                                                                                                                                                                                                                                                                                                                                          x − 2x − 3
                                                                                                                                                                                                                                                                                                                                                                                                                                2     2x − 6
                     You can add or subtract algebraic fractions when they have a                                                                                                                                                                                                                                   This method is similar to adding or                 ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••




                     common denominator.                                                                                                                                                                                                                                                                            subtracting numerical fractions.
                                                                                                                                                                                                                                                                                                                                                                         x 2 − 2x ÷ x 2 − 4 = x 2 − 2x × 2x − 6                                                                                                                                                                                                                                                           Multiply the first fraction by the
                                               +                                                                                                                                                                                                                                                                                                                        x − 2x − 3 2x − 6 x 2 − 2x − 3 x 2 − 4
                                                                                                                                                                                                                                                                                                                                                                              2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          reciprocal of the divisor.
                     E.g. b + y = by + by = ay by bx
                          a x     ay bx
                                                                                                                                                                                                                                                                                                                    by is the common denominator.
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 x(x − 2)       2(x − 3)
                                                                                                                                                                                                                                                                                                                                                                                                                                                                   =                        ×
                     You should find and use the lowest common denominator to                                                                                                                                                                                                                                                                                                                                                                                                 (x + 1)(x − 3) (x − 2)(x + 2)
                     keep the calculation as simple as possible.                                                                                                                                                                                                                                                                                                                                                                                                                   2x
                                                                                                                                                                                                                                                                                                                                                                                                                                                                   =
                                                                                                                                                                                                                                                                                                                                                                                                                                                                             (x + 1)(x + 2)
         EXAMPLE 1




                       Evaluate                                            a 3+1                                                                    b                2 + x−2
                                                                                         8                  6                                                      x2 + x x2 − 1
                       ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
                                                                                                                                                                                                                                                                                                                                                                      Exercise 1.1
                                                                                                                                                                                                                                                                                                                                                                      1 Simplify
                       a 3 + 1 = 9 + 4 = 13                                                                                                                                                                                                                                                                         The lowest common denominator
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              3p2q pq
                                     8                  6                   24                     24                        24                                                                                                                                                                                                                                                            6x 2 y
                                                                                                                                                                                                                                                                                                                    is 24.                                                  a                                                                                                                                                         b 8ab × 3ac
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          2     2                                                                                                                         c       ÷ 2
                                                                                                                                                                                                                                                                                                                                                                                           3xyz                                                                                                                                                          c                       4b                                                                                            2r  4r
                       b Factorise the algebraic expressions first:
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     ( b ) × a b− a
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    2
                                                2 + x−2 =       2         x−2                                                                                                                                                                                                                                                                                                                x × x +1                                                                                                                                                  a                                         2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                x + 3 × x −1
                                                                     +                                                                                                                                                                                                                                                                                                      d                                                                                                                                                         e                                                                                                                                   f
                                             x 2 + x x 2 − 1 x(x + 1) (x + 1)(x − 1)                                                                                                                                                                                                                                                                                                       x2 − 1 x2                                                                                                                                                                                     2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              x + x − 2 x2 + x − 6
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                2
C3




                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   C3
                                                                                                                                 2(x − 1)        x(x − 2)                                                                                                                                                           The lowest common denominator                                                x      ÷ x 2 + 2x
                                                                                                                                                                                                                                                                                                                                                                                                            2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      h 1 × x2 − 9 ÷ x + 3
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              2
                                                                                                                  =                          +                                                                                                                                                                                                                              g
                                                                                                                              x(x + 1)(x − 1) x(x + 1)(x − 1)                                                                                                                                                       is x(x + 1)(x - 1).                                                    x 2 − 5x + 6    x −4                                                                                                                                        x                 x − 3x                                               x

                                                                                                                  = 2x − 2 + x − 2x
                                                                                                                                                                            2

                                                                                                                                       x(x + 1)(x − 1)                                                                                                                                                                                                                2 Simplify and express as single fractions.
                                                                                                                                                                                                                                                                                                                                                                                 y
                                                                                                                 = x 2− 2
                                                                                                                    2
                                                                                                                                                                                                                                                                                                                                                                            a x+                                                                                                                                                       b a+b                                                                                                                              c    1 − 1
                                                                                                                                                                                                                                                                                                                                                                                            y                  z                                                                                                                                       b                  a                                                                                                   ax bx
                                                                                                                             x(x − 1)
                                                                                                                                                                                                                                                                                                                                                                            d               1 + 1                                                                                                                                      e                  1 +1                                                                                                            f     1 − 1
                                                                                                                                                                                                                                                                                                                                                                                           xy 2 x 2 y                                                                                                                                                   x +1 x                                                                                                                a −1 a +1
                     Multiplication and division                                                                                                                                                                                                                                                                                                                                             1         1
                                                                                                                                                                                                                                                                                                                                                                            g                    2 + a +1                                                                                                                              h 2+ 1                                                                                                                             i   3− 2
                     You do not need to have a common denominator when you                                                                                                                                                                                                                                          The method is similar to                                              (a + 1)                                                                                                                                                                        x                                                                                                           x +1
                     multiply or divide algebraic fractions.                                                                                                                                                                                                                                                        multiplying or dividing
                                                                                                                                                                                                                                                                                                                    numerical fractions.                                                      4 +2                                                                                                                                                        2 + 1                                                                                                               3+ 2
                                                                                                                                                                                                                                                                                                                                                                            j                                                                                                                                                          k                                                                                                                                  l
                                                                                                                                                                                                                                                                                                                                                                                            y −2 3                                                                                                                                                      x − 1 x2 − 1                                                                                                          x x2 + x
                     You can only cancel factors which are common to both the                                                                                                                                                                                                                                        Remember when cancelling
                     numerator and denominator.                                                                                                                                                                                                                                                                      brackets to cancel the whole                                                                                                                                                                                                         2 −     y                                                                                                                1
                                                                                                                                                                                                                                                                                                                     bracket and not just part of it.                       m                  1 −     2                                                                                                                               n                                                                                                                                  o              + 2 2
                                                                                                                                                                                                                                                                                                                                                                                             z + 1 z2 − z − 2                                                                                                                                           y + 2 y + 3y + 2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               x + 3x + 2 x + 4x + 3
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 2


                                                                                                                                                                                                                                                                                                                                                                                              3y      y +1
         EXAMPLE 2




                                                                                                                                                                                                                                                                                                                                                                            p                     +                                                                                                                                    q                    2z     − 2z                                                                                                   r   2+         1   − 1
                       Simplify                                          x + 2 × x(x 2 − 1)
                                                                                                                                                                                                                                                                                                                                                                                            y2 − 4 y2 + y − 2                                                                                                                                            z + 2z − 3 z − 1
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     x 2 + 2x x 2 − 4
                                                                         x2 − x  x2 − x − 6
                       ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••


                                                                                                                                                                                                                                                                                                                                                                      3 Simplify
                        x + 2 × x(x 2 − 1) = x + 2 × x(x − 1)(x + 1)                                                                                                                                                                                                                                                Factorise as much as you can
                        x2 − x  x 2 − x − 6 x(x − 1) (x + 2)(x − 3)                                                                                                                                                                                                                                                 before cancelling.                                                                                                                                   1+ 1
                                                                                                                                                                                                                                                                                                                                                                            a 1− x                                                                                     b    y                                                                                        c                x3 + 1                                                                         d x2 − 1 × x + 1
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        3


                                                                                                                  = x +1                                                                                                                                                                                                                                                      1− 1                                                                                                                                                                                                    x2 − 1                                                                            x +x         x −1
                                                                                                                                                                                                                                                                                                                     Cancel the fraction down to its                                                                                                                        1
                                                                                                                                                                                                                                                                                                                                                                                                                                                                         1− 2
                                                                                                                             x−3                                                                                                                                                                                     simplest form.                                              x                                                                                          y

     2                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         3
1 Algebra and functions

                                                                                                                                                                                                                                                                                                                                                                    Some divisions result in a remainder.
         1.2                              Algebraic division




                                                                                                                                                                                                                                                                                                                                                        EXAMPLE 2
                                                                                                                                                                                                                                                                                                                                                                      Divide                                    a 4037 by 16
                     You can use long division to divide a polynomial of degree m                                                                                                                                                                                                                                   The method is similar to dividing
                     by a polynomial of degree n, where m n.                                                                                                                                                                                                                                                        numbers using long division.                                                               b 4x3 + 3x + 7 by 2x - 1
                                                                                                                                                                                                                                                                                                                                                                      ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••



                     The degree of the resulting polynomial is m - n.                                                                                                                                                                                                                                                                                                 a                                                                   252
                                                                                                                                                                                                                                                                                                                                                                                                                                     16 4 0 3 7 )
                                                                                                                                                                                                                                                                                                                                                                                                                                        3 2↓↓
         EXAMPLE 1




                       Work out (x3 - 2x2 - x + 2) ÷ (x + 1)                                                                                                                                                                                                                                                                                                                                                                              83↓
                       ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
                                                                                                                                                                                                                                                                                                                                                                                                                                          80↓
                       Set out as a long division:                                                                                                                                                                                                                                                                                                                                                                                         37
                                                                                                                                                                                                                                                                                                                                                                                                                                           32
                                                                                                                                              )
                                                                                                                        x + 1 x 3 − 2x 2 − x + 2                                                                                                                                                                    Write each polynomial with the
                                                                                                                                                                                                                                                                                                                    highest power of x on the left.                                  So 4037 ¸ 16 = 252 remainder 5
                                                                                                                                                                                                                                                                                                                                                                                                                                             5                                                                                                                                                                                                                     The remainder is 5.


                       The lead term of x + 1 is x.                                                                                                                                                                                                                                                                                                                                                                                               = 252 5
                                                                                                                                                                                                                                                                                                                                                                                                                                                                             16
                       Divide the lead term x into x3 and write x2 in the answer space:
                                                                                                                                                                                                                                                                                                                                                                                    or                                   4037 = (252 ´ 16) + 5
                       Multiply this x2 by x + 1.             x2                                                                                                                                                                                                                                                    Write like terms in the

                               3 + x2 below and
                                                x + 1 x 3 − 2x 2 − x + 2
                                                                         Bring down the next
                                                                                                                                           )                                                                                                                                                                        same column.                                      b 4x3 + 3x + 7 does not have an x2-term.
                                                                                                                                                                                                                                                                                                                                                                                    Insert a 0x2 to fill the place value for x2:                                                                                                                                                                                                                                   The 0x2 is similar to the 0 in
                       Write x                        x3 + x2 ↓
                       subtract.                                         term -x.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  the number 4037, which
                                                           −3x − x
                                                              2
                                                                                                                                                                                                                                                                                                                                                                                                                                    2x 2 + x + 2
C3




                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           C3
                                                                                                                                                                                                                                                                                                                                                                                                                                                )
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   acts as place holder in the
                                                                                                                                                                                                                                                                                                                                                                                                                     2x − 1 4x 3 + 0x 2 + 3x + 7                                                                                                                                                                                                                   hundreds column.
                       Repeat this cycle until the division is complete.
                                                                                                                                                                                                                                                                                                                                                                                                                            4x 3 − 2x 2 ↓ ↓
                       The next step is to divide the lead term x into -3x2 and write - 3x in the                                                                                                                                                                                                                   Compare this method with the                                                                                   2x 2 + 3x ↓
                                                                                                                                                                                                                                                                                                                    numerical long division
                       answer space:                                                                                                                                                                                                                                                                                                                                                                                               2x 2 − x ↓
                                                                                                                                                                                                                                                                                                                                                                                                                                         4x + 7
                                                                                                                       x 2 − 3x + 2                                                                                                                                                                                      243
                                                                                                                                                                                                                                                                                                                                                                                                                                         4x − 2

                                                                                                                 x3 + x2 ↓ ↓
                                                                                                                                )
                                                                                                           x + 1 x 3 − 2x 2 − x + 2                                                                                                                                                                                    )
                                                                                                                                                                                                                                                                                                                    23 5 5 8 9
                                                                                                                                                                                                                                                                                                                       4 6↓ ↓
                                                                                                                                                                                                                                                                                                                         98↓
                                                                                                                                                                                                                                                                                                                                                                                                                                              9                                                                                                                                                                                                                    The remainder is 9.

                                                                                                                      −3x − x ↓
                                                                                                                          2                                                                                                                                                                                              9 2↓                                                                                4x 3 + 3x + 7 = 2x 2 + x + 2 remainder 9
                                                                                                                                                                                                                                                                                                                                                                                    So                                                                                                                                                                                                                                                                             You can also write this result as
                                                                                                                      −3x − 3x ↓
                                                                                                                          2                                                                                                                                                                                                69                                                                                    2x − 1
                        Subtract:                                                                                                                                                                                                                                                                                          69                                                                                                                                                                                                                                                                                                                                      4x3 + 3x + 7
                                                                                                                             2x + 2                                                                                                                                                                                         0                                                                                                 quotient    remainder                                                                                                                                                                                                                  = (2x - 1)(2x2 + x + 2) + 9
                                                                                                                             2x + 2                                                                                                                                                                                                                                                                                                                                                              ¯                                                      ¯
                                                                                                                                  0                                                                                                                                                                                 giving 5589 ÷ 23 = 243                                                                                                                                                                                                                                                                                                                         You can expand these brackets
                                                                                                                                                                                                                                                                                                                    or         5589 = 243 ´ 23                                                                                                                       = 2x + x + 2 + 9     2                                                                                                                                                                        to check your answer.
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   2x − 1
                       Since the remainder is 0, x + 1 is a factor of x3 - 2x2 - x + 2.                                                                                                                                                                                                                             Since the remainder is 0,
                                                                                                                                                                                                                                                                                                                    23 must be a factor of 5589.                                                                                                                                                                                                         -
                       So (x3 - 2x2 - x + 2) ÷ (x + 1) = x2 - 3x + 2                                                                                                                                                                                                                                                                                                                                                                                                                                                                           divisor
                       You could also write this result as x3 - 2x2 - x + 2 = (x + 1) ´ (x2 - 3x + 2)
                       You can then expand these brackets to check your answer.




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Maths_2

  • 1.
  • 2. 3 About this book Great Clarendon Street, Oxford OX2 6DP Oxford University Press is a department of the University of Oxford. Endorsed by Edexcel, this book is designed to help you achieve your best It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide in possible grade in Edexcel GCE Mathematics Core 3 and Core 4 units. Oxford New York The material is separated into the two units, C3 and C4. You can use the Auckland Cape Town Dar es Salaam Hong Kong Karachi tabs at the edge of the pages for quick reference. Kuala Lumpur Madrid Melbourne Mexico City Nairobi New Delhi Shanghai Taipei Toronto Each chapter starts with a list of objectives and a ‘Before you start’ With offices in section to check that you are fully prepared. Chapters are structured into Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore manageable sections, and there are certain features to look out for South Korea Switzerland Thailand Turkey Ukraine Vietnam within each section: © Oxford University Press 2009 The moral rights of the author have been asserted Key points are highlighted in a blue panel. Database right Oxford University Press (maker) First published 2009 Key words are highlighted in bold blue type. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, Worked examples demonstrate the key skills and techniques you need EXAMPLE 3 Divide 3x2 + 5 by x2 + 1 without the prior permission in writing of Oxford University Press, or as expressly permitted by law, or under terms agreed with the appropriate to develop. These are shown in boxes and include prompts to guide you •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Rewrite the numerator to involve a multiple of the denominator: reprographics rights organization. Enquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, through the solutions. 3x 2 + 5 = 3(x 2 + 1) + 2 x2 + 1 x2 + 1 Oxford University Press, at the address above Divide each term in the numerator: =3+ 2 You must not circulate this book in any other binding or cover Derivations and additional information are shown in a panel. x2 + 1 and you must impose this same condition on any acquirer British Library Cataloguing in Publication Data Data available Helpful hints are included as blue margin notes and sometimes as blue type ISBN-13: 9780-19-911784 0 within the main text. 1 3 5 7 9 10 8 6 4 2 Misconceptions are shown in the right Investigational hints prompt you to Printed in Great Britain by Ashford Colour Press, Ltd, Gosport. margin to help you avoid making explore a concept further. Paper used in the production of this book is a natural, recyclable product made from common mistakes. wood grown in sustainable forests. The manufacturing process conforms to the environmental regulations of the country of origin. Each section includes an exercise with progressive questions, starting Series Managing Editor Anna Cox with basic practice and developing in difficulty. Some exercises also include Acknowledgements ‘stretch and challenge’ questions marked with a stretch symbol The Publisher would like to thank the following for permission to reproduce and investigations to apply your knowledge in a variety of situations. INVESTIGATION photographs: 10 Use computer software or a graphical calculator to check P38 PA Archive/PA Photos; p74 Daniel Padavona/Shutterstock; p90 some of your answers to the questions in this exercise. studiovanpascal/iStockphoto; p120 Image Source/Corbis; p138 evirgen/iStockphoto; At the end of each chapter there is a ‘Review’ section which includes You may have to use abs (absolute value) button to input a modulus. p158 servifoto/iStockphoto; p178 Sylvanie Thomas/Shutterstock; p192 Dijital Film/iStockphoto; p206 Jenny Horne/Shutterstock; p212 Toni Räsänen/Dreamstime; exam style questions as well as past exam paper questions. There are also p260 pixonaut/iStockphoto; p267 Lawrence Freytag/iStockphoto; p274 Dmitry two ‘Revision’ sections per unit which contain questions spanning a Nikolaev/Shutterstock; p296 Hal Bergman/iStockphoto. range of topics to give you plenty of realistic exam practice. The cover photograph is reproduced courtesy of Frans Lemmens/Photodisc/Getty The final page of each chapter gives a summary of the key points, fully cross-referenced to aid revision. Also, a ‘Links’ feature provides an The publishers would also like to thank Kathleen Austin, Judy Sadler and Charlie Bond for their expert help in compiling this book. engaging insight into how the mathematics you are studying is relevant to real life. At the end of the book you will find full solutions and an index. The free CD-ROM contains a key word glossary and a list of essential formulae as well as additional study and revision materials and the student book pages.
  • 3. Contents C4 6 Partial fractions 147–158 10.8 Integration by parts 240 C3 6.1 Separating fractions 148 10.9 A systematic approach 6.2 More partial fractions 152 to integration 246 1 Algebra and 3 Exponentials and Review 6 156 10.10 Volumes of revolution 248 functions 1–38 logarithms 79–90 Exit 6 158 Review 10 256 1.1 Combining algebraic fractions 2 3.1 The exponential function, e x 80 Exit 10 260 1.2 Algebraic division 4 3.2 The logarithmic function, ln x 84 7 Parametric 1.3 Mappings and functions 8 3.3 Equations involving e x and ln x 86 equations 159–178 11 Differential 1.4 Inverse functions 16 Review 3 88 7.1 Parametric equations and equations 261–274 1.5 The modulus function 22 Exit 3 90 curve sketching 160 11.1 First-order differential equations 262 1.6 Solving modulus equations 7.2 Points of intersection 166 11.2 Applications of differential and inequalities 26 4 Differentiation 91–120 7.3 Differentiation 168 equations 268 1.7 Transformations of graphs 4.1 Trigonometric functions 92 7.4 Integration 172 Review 11 272 of functions 28 4.2 The exponential function, e x 98 Review 7 176 Exit 11 274 Review 1 34 4.3 The logarithmic function, ln x 102 Exit 7 178 Exit 1 38 4.4 The product rule 104 12 Vectors 275–296 4.5 The quotient rule 106 8 The binomial series 179–192 12.1 Basic definitions and notations 276 2 Trigonometry 39–74 4.6 The chain rule 110 8.1 The binomial series 180 12.2 Applications in geometry 282 2.1 Reciprocal trigonometric functions 40 4.7 Further applications 114 8.2 Using partial fractions 184 12.3 The scalar (dot) product 286 2.2 Trigonometric equations Review 4 118 8.3 Approximations 186 12.4 The vector equation of a and identities 46 Exit 4 120 Review 8 190 straight line 290 2.3 Inverse trigonometric functions 50 Exit 8 192 Review 12 294 2.4 Compound angle formulae 54 5 Numerical methods 121–138 Exit 12 296 2.5 Double angle and half angle 5.1 Graphical methods 122 9 Differentiation 193–212 formulae 60 5.2 Iterative methods 130 9.1 Differentiating implicit functions 194 Revision 4 297–306 2.6 The equivalent forms for Review 5 136 9.2 Differentiating parametric functions 198 a cos + b sin 66 Exit 5 138 9.3 Growth and decay 200 Answers 307 Review 2 70 9.4 Rates of change 206 Index 345 Exit 2 74 Revision 2 139–146 Review 9 210 Exit 9 212 CD-ROM Revision 1 75–78 Revision 3 213–216 The factor formulae 1–3 Formulae to learn 10 Integration 217–260 Formulae given in examination 10.1 The trapezium rule 218 Glossary 10.2 Integration as summation 222 C3 Practice paper 10.3 Integration using standard forms 224 C4 Practice paper 10.4 Further use of standard forms 226 10.5 Integration by substitution 228 10.6 Integration using trigonometric identities 232 10.7 Integration using partial fractions 238
  • 4. 1 Algebra and functions This chapter will show you how to combine algebraic fractions understand that some mappings are also functions find and use composite functions and inverse functions use the modulus function and sketch graphs involving it transform graphs of functions using translations, reflections, stretches and combinations of these. Before you start You should know how to: Check in: 1 Combine numerical fractions. 1 Calculate e.g. Calculate 3 + 1 = 9 + 2 = 11 a 3+2 C3 4 6 12 12 12 8 3 3 1 3 1 × = = 4 6 24 8 b 3×2 8 3 2 Find important facts to help you sketch 2 Sketch the graphs of graphs of functions. a y = x(x - 2) e.g. The graph of f(x) = 1 passes through the x−2 b y = x2 + x - 2 ( ) point 0, − 1 , has a vertical asymptote, x = 2, and 2 c y = 1 +2 x approaches the value 0 as x ® ± ¥ 3 Translate, reflect and stretch the graph 3 Write the equation of the image of the of y = f(x) graph of y = f(x) when e.g. When the graph of y = x2 is translated a f(x) = x2 is reflected in the x-axis +2 units parallel to the x-axis, its equation b f(x) = x2 - 5x is reflected in the y-axis becomes y = (x - 2)2 ⎛ −5 ⎞ c f(x) = x2 + x is translated by ⎜ ⎟ ⎝ 0⎠ d f(x) = x2 is stretched with scale factor 4 parallel to the y-axis. 1
  • 5. 1 Algebra and functions Dividing by a fraction is equivalent to multiplying by its reciprocal. 1.1 Combining algebraic fractions EXAMPLE 3 x 2 − 2x ÷ x 2 − 4 Addition and subtraction Simplify x − 2x − 3 2 2x − 6 You can add or subtract algebraic fractions when they have a This method is similar to adding or •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• common denominator. subtracting numerical fractions. x 2 − 2x ÷ x 2 − 4 = x 2 − 2x × 2x − 6 Multiply the first fraction by the + x − 2x − 3 2x − 6 x 2 − 2x − 3 x 2 − 4 2 reciprocal of the divisor. E.g. b + y = by + by = ay by bx a x ay bx by is the common denominator. x(x − 2) 2(x − 3) = × You should find and use the lowest common denominator to (x + 1)(x − 3) (x − 2)(x + 2) keep the calculation as simple as possible. 2x = (x + 1)(x + 2) EXAMPLE 1 Evaluate a 3+1 b 2 + x−2 8 6 x2 + x x2 − 1 •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Exercise 1.1 1 Simplify a 3 + 1 = 9 + 4 = 13 The lowest common denominator 3p2q pq 8 6 24 24 24 6x 2 y is 24. a b 8ab × 3ac 2 2 c ÷ 2 3xyz c 4b 2r 4r b Factorise the algebraic expressions first: ( b ) × a b− a 2 2 + x−2 = 2 x−2 x × x +1 a 2 x + 3 × x −1 + d e f x 2 + x x 2 − 1 x(x + 1) (x + 1)(x − 1) x2 − 1 x2 2 x + x − 2 x2 + x − 6 2 C3 C3 2(x − 1) x(x − 2) The lowest common denominator x ÷ x 2 + 2x 2 h 1 × x2 − 9 ÷ x + 3 2 = + g x(x + 1)(x − 1) x(x + 1)(x − 1) is x(x + 1)(x - 1). x 2 − 5x + 6 x −4 x x − 3x x = 2x − 2 + x − 2x 2 x(x + 1)(x − 1) 2 Simplify and express as single fractions. y = x 2− 2 2 a x+ b a+b c 1 − 1 y z b a ax bx x(x − 1) d 1 + 1 e 1 +1 f 1 − 1 xy 2 x 2 y x +1 x a −1 a +1 Multiplication and division 1 1 g 2 + a +1 h 2+ 1 i 3− 2 You do not need to have a common denominator when you The method is similar to (a + 1) x x +1 multiply or divide algebraic fractions. multiplying or dividing numerical fractions. 4 +2 2 + 1 3+ 2 j k l y −2 3 x − 1 x2 − 1 x x2 + x You can only cancel factors which are common to both the Remember when cancelling numerator and denominator. brackets to cancel the whole 2 − y 1 bracket and not just part of it. m 1 − 2 n o + 2 2 z + 1 z2 − z − 2 y + 2 y + 3y + 2 2 x + 3x + 2 x + 4x + 3 2 3y y +1 EXAMPLE 2 p + q 2z − 2z r 2+ 1 − 1 Simplify x + 2 × x(x 2 − 1) y2 − 4 y2 + y − 2 z + 2z − 3 z − 1 2 x 2 + 2x x 2 − 4 x2 − x x2 − x − 6 •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 3 Simplify x + 2 × x(x 2 − 1) = x + 2 × x(x − 1)(x + 1) Factorise as much as you can x2 − x x 2 − x − 6 x(x − 1) (x + 2)(x − 3) before cancelling. 1+ 1 a 1− x b y c x3 + 1 d x2 − 1 × x + 1 3 = x +1 1− 1 x2 − 1 x +x x −1 Cancel the fraction down to its 1 1− 2 x−3 simplest form. x y 2 3
  • 6. 1 Algebra and functions Some divisions result in a remainder. 1.2 Algebraic division EXAMPLE 2 Divide a 4037 by 16 You can use long division to divide a polynomial of degree m The method is similar to dividing by a polynomial of degree n, where m n. numbers using long division. b 4x3 + 3x + 7 by 2x - 1 •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• The degree of the resulting polynomial is m - n. a 252 16 4 0 3 7 ) 3 2↓↓ EXAMPLE 1 Work out (x3 - 2x2 - x + 2) ÷ (x + 1) 83↓ •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 80↓ Set out as a long division: 37 32 ) x + 1 x 3 − 2x 2 − x + 2 Write each polynomial with the highest power of x on the left. So 4037 ¸ 16 = 252 remainder 5 5 The remainder is 5. The lead term of x + 1 is x. = 252 5 16 Divide the lead term x into x3 and write x2 in the answer space: or 4037 = (252 ´ 16) + 5 Multiply this x2 by x + 1. x2 Write like terms in the 3 + x2 below and x + 1 x 3 − 2x 2 − x + 2 Bring down the next ) same column. b 4x3 + 3x + 7 does not have an x2-term. Insert a 0x2 to fill the place value for x2: The 0x2 is similar to the 0 in Write x x3 + x2 ↓ subtract. term -x. the number 4037, which −3x − x 2 2x 2 + x + 2 C3 C3 ) acts as place holder in the 2x − 1 4x 3 + 0x 2 + 3x + 7 hundreds column. Repeat this cycle until the division is complete. 4x 3 − 2x 2 ↓ ↓ The next step is to divide the lead term x into -3x2 and write - 3x in the Compare this method with the 2x 2 + 3x ↓ numerical long division answer space: 2x 2 − x ↓ 4x + 7 x 2 − 3x + 2 243 4x − 2 x3 + x2 ↓ ↓ ) x + 1 x 3 − 2x 2 − x + 2 ) 23 5 5 8 9 4 6↓ ↓ 98↓ 9 The remainder is 9. −3x − x ↓ 2 9 2↓ 4x 3 + 3x + 7 = 2x 2 + x + 2 remainder 9 So You can also write this result as −3x − 3x ↓ 2 69 2x − 1 Subtract: 69 4x3 + 3x + 7 2x + 2 0 quotient remainder = (2x - 1)(2x2 + x + 2) + 9 2x + 2 ¯ ¯ 0 giving 5589 ÷ 23 = 243 You can expand these brackets or 5589 = 243 ´ 23 = 2x + x + 2 + 9 2 to check your answer. 2x − 1 Since the remainder is 0, x + 1 is a factor of x3 - 2x2 - x + 2. Since the remainder is 0, 23 must be a factor of 5589. - So (x3 - 2x2 - x + 2) ÷ (x + 1) = x2 - 3x + 2 divisor You could also write this result as x3 - 2x2 - x + 2 = (x + 1) ´ (x2 - 3x + 2) You can then expand these brackets to check your answer. 4 5