I am having trouble with this problem
Use a graphing utility to graph the function on the closed interval [a, b].
f (x) =(x/2)-sin(pi*x/6) [−1, 0]
Determine whether Rolle's Theorem can be applied to f on the interval.
If Rolle's Theorem can be applied, find all values of c in the open interval (a, b) such that f '(c) = 0. (Enter your answers as a comma-separated list. Round your answers to four decimal places. If not possible, enter IMPOSSIBLE.)