ACHER PRACTICE ANOTHE Consider the following. f(x) = 3x\\ 4-x2, [-2, 2] (a) Use a computer algebra system to differentiate the function. f' ( x ) = (b) Sketch the graphs of f and f' on the same set of coordinate axes over the given interval. Use a graphing utility to find the critical numbers of f in the open interval (-2, 2). (Enter your answers as a comma-separated list.) X = (c) Find the open interval(s) on which f' is positive and the open interval(s) on which f' is negative. (Enter your answers using interval notation.) positive negative Compare the behavior of f and the sign of f'. O f is increasing when f' is positive and decreasing when f' is negative. O f is positive when f' is positive and negative when f' is negative. O f is increasing when f' is increasing and decreasing when f' is decreasing. Of is decreasing when f' is positive and increasing when f' is negative. O f is increasing when f' is decreasing and decreasing when f' is increasing. une