Consider the following function. f(x) (4x+2, x-3, x -1 x > -1 (a) Find the critical numbers of f. (Enter your answers as a comma-separated list.) x = 4 (b) Find the open intervals on which the function is increasing or decreasing. (Enter your answers using interval notation. If an answer does not exist, enter DNE.) increasing DNE x decreasing (-1,0] x (c) Apply the First Derivative Test to identify the relative extremum. (If an answer does not exist, enter DNE.) relative maximum (x, y) = DNE relative minimum (x, y) = = * )