Use derivatives to: A. Identify the x-value(s) where the extrema of f(x) = x³-12x+8 occur. B. Find the point(s) at which f(x) = x³-12x+8 C. Find the interval(s) where f(x)= x³-12+8 is increasing on [-5,5] D. Find the point(s) of inflection forf(x)= x³-12+8. E. Find the interval(s) wheref(x)= x³-12+8 is concave down on (-inf,+inf)