題組內容

6. Suppose that f(x) is continuous on [0,6] and f(0) = f(4) = 0. The graph of f'(x) is given as below, but values of f'(1), f"(2) and f'(4) are not determined. It is known that

(b)  List all critical numbers of f(x) in the interval (0, 6). Where does f(x) attain a local maximum? Where does f(x) attain a local minimum?