Math 1100
Homework 32
Name:
1. (12 points) Let z = ln(xy) − x2 y Compute the following derivatives.
(a) zx
(b) zy
(c) zxx
(d) zxy
(e) zyx
(f) zyy
9 December, 2013
2. Suppose the total cost of producing a product is
C(x, y) = 25 + 2x2 + 3y 2
where x is the cost per pound for material and y is the cost per hour for labor.
(a) If material costs are held constant, at what rate will the total cost increase for each
$1 increase in the per-hour cost of labor?
(b) If labor costs are held constant, at what rate will the total cost increase for each $1
per pound increase in the cost of materials?