4. (10 points) Consider the Motion f(:] = gxs 3:2 +33 + 4 (:1) Find the derivative of n): fix} = (b) Find the critics] points of f, i.e., solve for the values x such that f'(m) = I]: (c) Sketch the graph of y = u): I! 4 1 i [d] For what values of x is f'(:b) > 0'? Note that these are the values of .1 for which x) is increasing. [8) For what values of z is f'($]