Let f(x) = -6x3 + 6x for x

Let 62 for x < O, 5t2 4 for 'c O. According to the definition of the derivative, to compute f '(0), we need to compute the left-hand limit lim which is and the right-hand limit We conclude that f' (O) is undefined Note: If a limit or derivative is undefined, enter 'undefined' as your answer.