Chapter 1.2, Problem 22ES

4. Find the general solution and the definite solution for the following differential equations: (a) +10y=15, y(0) = 0; (b) 2 + 4y = 6, y(0) =

5) For each function represented by an equation, make a table and plot the corresponding points to sketch the graph of the function. (a) y = 75 ()* 220 X y 200- -2 180 160 -1 140 0 120 100 1 60 80 2 3 4 x (b) y = 20 ()* 1 60 40 20 20 0 2 3 65- -1 X y 60 -2 55- 50 45 44 40 0 35- 30 1 25 2 20 20 15 3 10 5 LO 4 3-2 T -1 0 5- 4- -3- 2-

5. Find the solution to each of the following by using an appropriate formula developed in the lecture slides: (a) + 3y = 2, y(0) = 4; (b) dy - 7y = 7, y(0) = 7; (c) 3d+6y= 5, y(0) = 0

1. Evaluate the following improper integrals: (a) fe-rt dt; (b) fert dt; (c) fi da dx

8. Given the rate of net investment I(t) = 9t¹/2, find the level of capital formation in (i) 16 years and (ii) between the 4th and the 8th years.

9. If the marginal revenue function of a firm in the production of output is MR = 40 - 10q² where q is the level of output, and total revenue is 120 at 3 units of output, find the total revenue function. [Hints: TR = √ MRdq]

6. Solve the following first-order linear differential equations; if an initial condition is given, definitize the arbitrary constant: (a) 2 + 12y + 2et = 0, y(0) = /; (b) dy+y=t

4. Let A = {a, b, c, d, e, f}, B = {e, f, g, h} and C = {a, e, h,i}. Let U = {a, b, c, d, e, f, g, h, i, j, k}. • Draw a Venn Diagram to describe the relationships between these sets Find (AB) NC • Find (AC) UB Find AUBUC • Find (BC) N (A - C)

7. A consumer lives on an island where she produces two goods x and y according to the production possibility frontier x² + y² < 200 and she consumes all the goods. Her utility function is U(x, y) = x y³. She faces an environmental constraint on her total output of both goods. The environmental constraint is given by x + y ≤20. • (a) Write down the consumer's optimization problem. (b) Write out the Kuhn-Tucker first order conditions. (c) Find the consumer's optimal consumption bundle (x*, y*).