Let f(x) = 5x3 - 2x. (d) Critical Point Classification: f is has local maximums at I = 1 E f is has local minimums at I = 0 E f is has critical points that are neither local mins nor maxes at I = (1,3)(0,0) incorrect Single point intervals must use T and T (e) Concavity: f is concave up for I E NONE f is concave down for I E (-INF, INF)