3. (6 pts.) Let f(x) = x2(In x - 1). (a) Find the critical numbers of f. (b) Find the open interval(s) on which f is increasing and the open interval(s) on which f is decreasing. (c) Find the local minimum value(s) and local maximum value(s) of f, if any. (d) Find the open interval(s) where f is concave upward and the open interval(s) where f is concave ownward