hello. i am not quite sure how to solve these problems when they aren't revolving around the x or y axis. for example: area within y=x^4 , y=1 revolving around y=8 What do I do?
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Originally Posted by thedoge hello. i am not quite sure how to solve these problems when they aren't revolving around the x or y axis. for example: area within y=x^4 , y=1 Revolving $\displaystyle x^4$ about line $\displaystyle y=1$. Is the same as revolving $\displaystyle x^4-1$ about the line $\displaystyle y=0$ (x-axis). Think of this as a picture. Thus, $\displaystyle \pi \int_{-1}^1 (x^4-1)^2 dx$
Well, that's what I thought too, but apparently my answer is wrong. Came out to 4.4680?
Try using shells. $\displaystyle 2{\pi}\int_{0}^{1}(x-8)(x^{4}-1)dx$
Last edited by galactus; Nov 24th 2008 at 05:39 AM.
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