9. The Mean Value Theorem for Derivatives f ( c) = 1(b)- f(a) b - a The slope of the tangent at c equals the slope of the secant through a and b. 35. If f is continuous and differentiable for all values on (2,5) and f(2) =-3, f(3) =4 and f(5) =-3, then on the interval (2,5). a. What can be said about the slope? b. How many extrema? 36. Find the average rate of change for f(x) =-x2 -4x+3on [-2, 0]. (slope of the secant line) 37. For what value c, such that O