Consider the following function. f(X) ={4x+ 1, XS 1 x24, x>1 (a) Find the critical numbers of f. (Enter your answers as a comma-separated list.) x=0 X (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 (00, 1),(0,00) J decreasing ( 1,0) J (c) Apply the First Derivative Test to identify the relative extremum. (If an answer does not exist, enter DNE.) relative maximum (X, Y) = ( _1a _ 3 ) V relative minimum (x, y) = ( 0. Z ) X