If Rolle's Theorem can be applied, find all values of c in the open interval (a, b). such that f '(c) = 0. (Enter your answers as a comma-separated list. If Rolle's Theorem cannot be applied, enter NA.)
f(x) = (x-2)(x-3)(x-6), [2,6]
After multiplying out f(x) I got: x^3 -11x^2 +36x -36
