Lets continue now with Question 1 Part B.
Part be asks that we revolve f(x) and g(x) around the x-axis. To do this, must integrate f(x)^2 - g(x)^2 using the same parameters as Part A (0 to .94194). Then, after it is integrated, we must multiply it by pi.
Remember that the first part of the AP Calculus free response allows you to use a graphing calculator. A graphing calculator is actually required to solve this problem because the indefinite integral of e^(-x^2) can not be found.
Back to the problem... just put in the definite integral in your calculator and press enter. If you have a TI-83 Plus or TI-84 Plus, type fnInt((e^((-2x)^2)-((1-cos(x))^2),x,0,.94194).
You should get Volume = 1.7466 units^3