- #1

robertmatthew

- 48

- 0

## Homework Statement

Use cylindrical shells to find the volume of a torus with radii r and R.

## Homework Equations

V= ∫[a,b] 2πxf(x)dx

y= sqrt(r

^{2}- (x-R)

^{2})

## The Attempt at a Solution

V= ∫ [R, R+r] 2πx sqrt(r

^{2}- x

^{2}- 2xR + R

^{2}) dx

I feel like this isn't going in the right direction, though. I found a different post about the same question, but that person was using disks, and the volume was 2π

^{2}r

^{2}R, and I can't see where the π

^{2}would come from in my equation, so I think I'm going about this incorrectly. Any help is much appreciated, thanks.