Find the volume created by revolving:(adsbygoogle = window.adsbygoogle || []).push({});

[tex] y=x^2 +x - 2 [/tex]

and y=0 about the x axis.

[tex] y=x^2 +x - 2 [/tex] intersects the x axis at -1 and 1 so those are the bounds of integration.

the radius of the figure = -([tex] y=x^2 +x - 2 [/tex])

so:

V = [tex] - \pi \int_{-1}^1 (x^2 + x - 2)^2 dx [/tex]

After integrating that I get 18[tex]\pi[/tex]/5. The actual answer is 81[tex]\pi[/tex]/10. What I want to know is if i set the integral up right. If I did then this is only a stupid integration mistake. If not then I hope someone finds my mistake. Thanks for the help.

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# Homework Help: Volume of revolution problem

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