Find where the global max and global min of the function occur (on the specified interval).
on the interval [-1,4]
The derivative is
This is 0 when -x3 = -1, or when x = 1. This is our only critical point, since anywhere f' is undefined, f is already undefined.
The function f achieves its global max on this interval when x = 1 and its global min when x = -1.