Use the alternative form of the derivative to find the derivative at x = c (if it exists). (If the derivative does not exist at c, enter UNDEFINED.) h (x) = 1x + 71, c= -7 h' ( - 7) =Describe the x-values at which the function is differentiable. (Enter your answer using interval notation.) f ( x) = (x+ 4)2/3 4 2 1 X -8 -6 -4 - 2 -2