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Sequences




     Photo source chromaspiral
Find the next three terms in each sequence of numbers ...



                       4, 7, 10, 13,        ,       ,


                       3, 6, 12, 24,       ,        ,


                       32, 16, 8, 4,        ,       ,



                   1, 1, 2, 3, 5, 8,13,         ,   ,
4, 7, 10, 13,   ,   ,
Sequence: An ordered list of numbers that follow a certain pattern (or rule).

Arithmetic Sequence:(i) Recursive Definition: An ordered list of numbers
          generated by continuously adding a value (the common
          difference) to a given first term.
          (ii) Implicit Definition: An ordered list of numbers where
          each number in the list is generated by a linear equation.

Common Difference (d):(i) The number that is repeatedly added to
        successive terms in an arithmetic sequence.
        (ii) From the implicit definition, d is the slope of the linear
        equation.
To Find The Common Difference
  d = tn - t(n - 1)
  d is the common difference
  tn is an arbitrary term in the sequence
  t(n - 1) is the term immediately before tn in the sequence

To Find the nth Term In an Arithmetic Sequence
  tn = a + (n - 1)d
  tn is the nth term
  a is the first term
  n is the quot;rankquot; of the nth term in the sequence
  d is the common difference

  Example: Find the 51st term (t51) of the sequence 11, 5, -1, -7, ...
  Solution:   a = 11             t51 = 11 + (51 - 1)(-6)
              d = 5 - 11         t51 = 11 + (50)(-6)
                = -6             t51 = 11 - 300
              n = 51             t51 = -289
3, 6, 12, 24,   ,   ,




32, 16, 8, 4,   ,   ,
Geometic Sequence: (i) Recursive Definition: An ordered list of numbers
       generated by continuously multiplying a value (the common ratio)
       with a given first term.
       (ii) Implicit Definition: An ordered list of numbers where each
       number in the list is generated by an exponential equation.

Common Ratio (r): (i) The number that is repeatedly multiplied to
      successive terms in a geometic sequence.
     (ii) From the implicit definition, r is the base of the exponential
     function.
To Find The Common Ratio


  r is the common ratio
  tn is an arbitrary term in the sequence
  t(n - 1) is the term immediately before tn in the sequence

To Find the nth Term In a Geometic Sequence


  tn is the nth term
  a is the first term
  n is the quot;rankquot; of the nth term in the sequence
  r is the common ratio

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Pre-Cal 40S Slides May 29, 2007

  • 1. Sequences Photo source chromaspiral
  • 2. Find the next three terms in each sequence of numbers ... 4, 7, 10, 13, , , 3, 6, 12, 24, , , 32, 16, 8, 4, , , 1, 1, 2, 3, 5, 8,13, , ,
  • 3. 4, 7, 10, 13, , ,
  • 4. Sequence: An ordered list of numbers that follow a certain pattern (or rule). Arithmetic Sequence:(i) Recursive Definition: An ordered list of numbers generated by continuously adding a value (the common difference) to a given first term. (ii) Implicit Definition: An ordered list of numbers where each number in the list is generated by a linear equation. Common Difference (d):(i) The number that is repeatedly added to successive terms in an arithmetic sequence. (ii) From the implicit definition, d is the slope of the linear equation.
  • 5. To Find The Common Difference d = tn - t(n - 1) d is the common difference tn is an arbitrary term in the sequence t(n - 1) is the term immediately before tn in the sequence To Find the nth Term In an Arithmetic Sequence tn = a + (n - 1)d tn is the nth term a is the first term n is the quot;rankquot; of the nth term in the sequence d is the common difference Example: Find the 51st term (t51) of the sequence 11, 5, -1, -7, ... Solution: a = 11 t51 = 11 + (51 - 1)(-6) d = 5 - 11 t51 = 11 + (50)(-6) = -6 t51 = 11 - 300 n = 51 t51 = -289
  • 6. 3, 6, 12, 24, , , 32, 16, 8, 4, , ,
  • 7. Geometic Sequence: (i) Recursive Definition: An ordered list of numbers generated by continuously multiplying a value (the common ratio) with a given first term. (ii) Implicit Definition: An ordered list of numbers where each number in the list is generated by an exponential equation. Common Ratio (r): (i) The number that is repeatedly multiplied to successive terms in a geometic sequence. (ii) From the implicit definition, r is the base of the exponential function.
  • 8. To Find The Common Ratio r is the common ratio tn is an arbitrary term in the sequence t(n - 1) is the term immediately before tn in the sequence To Find the nth Term In a Geometic Sequence tn is the nth term a is the first term n is the quot;rankquot; of the nth term in the sequence r is the common ratio