Suppose a ?rm’s cost function is given by C(Q) = Q^2 + 100 over the interval [0,10]. Sketch this function and then draw a secant line that connects the points 1 and 5.
(a) What is the range of this cost function?
(b) Using the equation for the average rate of change along a secant line, solve for the cost C’ that you get along the above secant line for Q=3.
(c) Is this function concave or convex? How do you know this?