I am having trouble with this problem

Use a graphing utility to graph the function on the closed interval [a,b].

(f) =(x/2)-sin(pi*x/6) [−1, 0]x

Determine whether Rolle's Theorem can be applied tofon the interval.

If Rolle's Theorem can be applied, find all values ofcin the open interval (a,b) such thatf '(c) = 0. (Enter your answers as a comma-separated list. Round your answers to four decimal places. If not possible, enter IMPOSSIBLE.)