x2 - 2x + 1 if x51 4. Consider the function f(x =

4. Consider the function x -2V+1 2x3 - a x2 _ if I < x < 4 L x 4 + x2 +9x24 if 4 f x Discuss the continuity and differentiability of the function at x = 1 and x - 4. Prove your assertions mathematically (a graphic proof will NOT suffice).