math
posted by alexis .
The region between the graphs of y=x^2 and y=2x is rotated around the line x=2.
how do you find the volume of the object?

First find the enclosed region between the curves. It looks like it goes from (x = 0, y = 0) to (x = 2, y = 4)
Then perform the integration from x = 0 to 2 of 2 pi(2x  x^2)(2x)dx. This is a series of thin ringshaped areas centered on the x=2 vertical line