Let f (x) be a function that is differentiable everywhere and has a derivative f'(x) = 3x² + 14x + 6.
Verify that the Intermediate Value Theorem for Derivatives applies to the function f' (2) on the interval
[-6, -3], and find the value of c guaranteed by the theorem such that f' (c) = -2

I also attached the work that I've done so far, but I don't think that it's right.