exercise 3 for 2b2d

2. Find f, and fy from the following: 2x - 3y (a) f( x, y) = x2 + 5xy- y3 (c) f ( x, y) = x +y X (b) f (x, y) = (x2 - 3y)(x - 2) (d) f ( x, y) = xy 3. From the answers to Prob. 2, find f (1, 2)-the value of the partial derivative f, when x = 1 and y = 2-for each function