- #1

- 27

- 0

## Homework Statement

An ellipse is rotated around the y-axis, find the volume of this solid.

## Homework Equations

x^2 / a^2 + y^2 / b^2 = 1

[tex]

\pi\int_{a}^-a x^2 dy

[/tex]

## The Attempt at a Solution

I'm having trouble solving this; I know that the upper and lower bounds of the curve occur on the y-axis so I think that the ellipse equation can be rearranged to form;

x^2 / a^2 + 0 = 1

Thats where the upper and lower bounds for the integral come from.

However I know that the volume of an ellipsoid is V = 4/3*pi*a*b^2.

I just can't seem to get it to work.

Any help is appreciated :)