please help me solve this.

4. (13 point) Consider the function f(x) = 12 NR. + x - 1 a) (4 point) Find all the critical values of f. b) (3 point) For each critical value, say whether it is a minimum, a maximum or an inflexion point. d) (3 point) What are all the inflexion points of f? e) (3 point) Draw f (as well as possible), indicating the critical points and the value of f at those points