1. Set of problems
Maths for Economics and Business
Vilnius-Kaunas (Lithuania) 2009/2010
MATHEMATICS
FOR ECONOMICS AND BUSINESS
SET OF EXERCISES
Spring Semester 2010
Lecturer P_ U_E_ R _T _A _S, J. M_I_Q_U_E_L.
THE following set of problems is based on the book Ian Jacques “Mathematics
for Economics and Business” (5th Edition) Prentice Hall.
The set of problems has to be hand in to the Lecturer by 15 th of June (by mail) or
in a hard copy to the Academic Department. If you hand in the set of
problems, that is optional, you can get till 2 extra points that will be added to
the mark obtained at the final exam.
The completion of the set of exercises is optional but it may help the students to
improve their marks.
EVALUATION CRITERIA:
A) 0.5 points if the student hand in the exercises before the dead-.line. If the
student hand in the exercises after the dead-line he/she will not get any
additional point.
B) 1.5 points if there are not important mistakes in the answers.
0.75 points if there are some important mistakes in the answers.
0.25 points if there are many important mistakes.
0 points if the student doesn’t hand in the exercises before or after the
dead-line.
I wish you good luck!!
(1)Picture: “2+2 is 5” taken in Kaunas (on a wall besides “Blues & Orange” Baras ) in Kaunas old
town.. Lithuania. September 2009.
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2. Set of problems
Maths for Economics and Business
Vilnius-Kaunas (Lithuania) 2009/2010
1rst. Exercise: Check section 2.1 Quadratic functions.
Use “the formula” to solve the following quadratic equations (Round your answers to 2 decimal
places).The “formula” to solve quadratic equations is
a)
b)
c)
d)
e)
2ond. Exercise: Check Section 2.1: Quadratic functions. Page 126
Given the supply and demand functions
+18 +14
8 +120
calculate the equilibrium price and quantity
3rd. Exercise: Check section 4.3: Marginal function.
If the production function is
Where Q denotes output and L denotes the size of the workforce, calculate the value of MPL
(marginal product of labour) when
a) L=1
b) L=10
c) L=100
d) L=2000
4th. Exercise: Check section 2.2 Revenue cost and profit.
If fixed costs are 6, variable costs per unit are 2 and demand function is
Obtain an expression of ∏ (profit) in terms of Q and hence sketch a graph of ∏ against Q.
a) For what values 0f Q does the firm break even?
b) What is the maximum profit?
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3. Set of problems
Maths for Economics and Business
Vilnius-Kaunas (Lithuania) 2009/2010
5th Exercise: Check Section 4.2: Rules of differentiation
Differentiate
a)
b)
c)
d)
e)
f)
6 th. Exercise: Check the section 7. Basic matrix operations Page 465-467
Let
Find (where possible)
a) AB
b) BA
c) CD
d) DC
e) AC
f) CA
7 th. Exercise: Check section 7.2: Matrix inversion (page 475)
The equilibrium price P1 and P2 for two goods satisfy the equations
Express this system in matrix form and hence find the values of and
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4. Set of problems
Maths for Economics and Business
Vilnius-Kaunas (Lithuania) 2009/2010
8th exercise: Check section 5.6: Lagrange multipliers. Page 412
Use Lagrange multipliers to find the optimal value of
Subject to the constraint
9 th. Exercise: Check section 7.3: Cramer’s rule. Page 493
Solve the system of equations
=
Using Cramer’s rule to find
10th Exercise: Check section 5.2: Partial elasticity and marginal functions. Page 360.
Given the utility function
Determine the value of the marginal utilities
and
When =300. Hence estimate the change in utility when
decreases
from 200 to 199 and increases from 300 to 301.
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