Volume of Solid Revolved Around Y-Axis: Bounds Check

Saladsamurai
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find the volume of the solid resulting when the region enclosed by the curves is revolved around y-axis.

x=\sqrt{1+y} x=0 y=3

I am using this integral...

V=\int_{-1}^3[\pi(\sqrt{1+y})^2]dy

and I am getting the wrong answer.

I think it is just arithmetic, but are my bounds correct?

Thanks,
Casey
 
Last edited:
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Just wondering about the bounds here..
 
Your bounds&integral look fine to me.
You should get something like V=\pi(3+\frac{9}{2}+1-\frac{1}{2})=8\pi
 
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