Math for Econ I, Homework Assignment New York University Please write neat solutions for the problems below. Show all your work. If you only write the answer with no work, you will not be given any credit. Write your name and recitation section number. Staple your homework if you have multiple pages! 1. (5 pts) Let f (x, y) = x2 y 2 . Find fy (a, b) using the definition of the partial derivative with respect to y. 2. (5 pts) Any way you wish, find fx (x, y) and fy (x, y) if f (x, y) = (1 + ln(x) + y 2 )xy . 3. If the price of a product is p (dollars), the number of units demanded is given by the equation f (p) = pe3p . (a) (2 pts) Find the elasticity of f with respect to p by using the derivative definition of elasticity. Fully simplify your answer. (b) (3 pts) Use your answer from part (a) to estimate the percent change in f when the price is raised from $2.00 to $2.20