Volume Question (Can someone check my work?)

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The volume of the solid within the sphere x^2+y^2+z^2=4, above the x-y plane, and below the cone z=\sqrt{x^2+y^2} was correctly set up using polar coordinates. The calculations involved two integrals, leading to the result V=\frac{8\pi\sqrt{2}}{3}. The method used is considered appropriate for this problem. Additionally, there is no simpler single double integral approach suggested for this specific volume calculation. The solution is validated as correct.
amcavoy
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I posted this in the Calculus section also, so I apologize for double-posting.

"Find the volume of the solid that lies within the sphere x^2+y^2+z^2=4, above the x-y plane, and below the cone z=\sqrt{x^2+y^2}."

I set this up in polar coordinates as follows:

V=\int_{0}^{2\pi}\int_{0}^{\sqrt{2}}r^2drd\theta+\int_{0}^{2\pi}\int_{\sqrt{2}}^{2}r\sqrt{4-r^2}drd\theta

and then solved it coming up with V=\frac{8\pi\sqrt{2}}{3}.

Is this the correct way to set this up? Also, is there a way I could do this with one double integral rather than adding two of them together?

Thanks for your help.
 
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apmcavoy said:
I posted this in the Calculus section also, so I apologize for double-posting.

"Find the volume of the solid that lies within the sphere x^2+y^2+z^2=4, above the x-y plane, and below the cone z=\sqrt{x^2+y^2}."

I set this up in polar coordinates as follows:

V=\int_{0}^{2\pi}\int_{0}^{\sqrt{2}}r^2drd\theta+\int_{0}^{2\pi}\int_{\sqrt{2}}^{2}r\sqrt{4-r^2}drd\theta

and then solved it coming up with V=\frac{8\pi\sqrt{2}}{3}.

Is this the correct way to set this up? Also, is there a way I could do this with one double integral rather than adding two of them together?

Thanks for your help.

It is correct, and I think that was the simplest way to solve.

ehild
 
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