Consider the function an) : 4(33 492/3. (a) Find all critical numbers c of f. c = (b) f is increasing for a: E (c) f is decreasing for a: 6 (cl) f is concave up for a: E (e) f is concave down for a: 6 Note: Input U, infinity, and -infinity for union, co, and 00, respectively. If there are multiple answers, separate them by commas. If there is no answer, input none. Consider the function at) : 2.122 2:34. (a) Find all critical numbers c of f. c : (b) f is concave up for 93 E (c) f is concave down for m E (d) Using the 2nd derivative test, the local maxima off occur at :r: : (e) Using the 2nd derivative test, the local minima of f occur at a: : Note: Input U, infinity, and -infinity for union, co, and 00, respectively. If there are multiple answers, separate them by commas. If there is no answer, input none