Use Qesmgs to graph a cubic polynomial function, f (I) of your choice and its I derivative, f (it?) and explain the changes that happened. For example, if 33 = a is I where f (I) has an extreme value (max or min) then what happened to f (:8) at 13 = a. Explain the following: - If f (1') is increasing or decreasing in an interval then what happens to I f (I) in those intervals? I - Isf (3}) above or below the xaxis, and why? Then repeat with the graph a polynomial function, f (I) of degree 4 and repeat the same exercises. Show your work in full for maximum credit