(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hi, the next problem I thought it was easy...and I really think it is, but I haven't come with the right answer :S. I compare the answer in an internet page of problems and all it says is "wrong"...

The problem is the following:

Find the volume of the solid obtained by rotating the region bounded by

y=8*x+32, y=0 about the y-axis.

2. Relevant equations

I made the sketh in Maple:

http://img109.imageshack.us/img109/5669/solidvolumexi5.th.jpg [Broken]

3. The attempt at a solution

Then I solve for x:

x=(y/8)-4

and wrote the Integral with respect to y, and limits from 0 to 32 (where the function y=8x+32 intersects the y-axis).

Integral of Pi*f(x)^2, from y=0 to y=32, it should give me the volume, isn't it?

http://img164.imageshack.us/img164/98/equationie6.th.jpg [Broken]

My answer: 512/3 * Pi= 536.1651462

But the internet page says I'm wrong but I don't know why :S

Any help is welcome, Thanks in advance!

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# Volume of a Solid by Revolution

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