Find the marginal utility functions of the following utility functions:
Plot the marginal utility functions. Indicate which of these functions appear to exhibit diminishing, constant or increasing marginal utility?
1. u(x,y) = 3x + 2y
2. u(F,C) = 10FC
3. u(F,C) = .2F2C2
4. u(x,y) = (XY)1/2