### Home > APCALC > Chapter 8 > Lesson 8.1.5 > Problem8-53

8-53.

When setting up a problem to compute volume by the washer method, explain why $\pi \int _ { a } ^ { b } ( R ^ { 2 } - r ^ { 2 } ) d x$ is not equivalent to $\pi \int _ { a } ^ { b } ( R - r ) ^ { 2 } d x$.

Is $(R^2-r^2)=(R-r)^2$?