# How do you find the volume of a solid of revolution washer method?

Aug 30, 2014

Suppose that $f \left(x\right) \ge q g \left(x\right)$ for all $x$ in $\left[a , b\right]$. If the region between the graphs of $f$ and $g$ from $x = a$ to $x = b$ is revolved about the $x$-axis, then the volume of the resulting solid can be found by
$V = \pi {\int}_{a}^{b} \left\{{\left[f \left(x\right)\right]}^{2} - {\left[g \left(x\right)\right]}^{2}\right\} \mathrm{dx}$