Washer Method: Revolving Around x/y Axes Practice Test

$\pi\int_{1}^{2}\left[\left(\tfrac{y}{2}+2\right)^2-\left(\tfrac{2}{y}+5\right)^2\right]dy$

$\pi\int_{1}^{2}\left(\tfrac{2}{y}+5\right)^2dy$

$\pi\int_{1}^{2}\left[\left(\tfrac{2}{y}+5\right)^2-\left(\tfrac{y}{2}+2\right)^2\right]dy$

$\pi\int_{1}^{2}\left[\left(\tfrac{2}{y}+5\right)-\left(\tfrac{y}{2}+2\right)\right]^2dy$

$\pi\int_{1}^{2}\left[\left(\tfrac{2}{y}+5\right)^2+\left(\tfrac{y}{2}+2\right)^2\right]dy$