Determine whether the Mean Value Theorem can be applied to f on the closed interval [a, b]. If the Mean Value Theorem can be applied, find all values of c in the open interval (a, b) such that f '(c) =( f(b) - f(a) )/b-a . If the Mean value Theorem cannot applied, explain why not.
f(x) = x^3 + 2x, [-1,1]