Solving for Volume in a Complex Figure: Ostrogradsky and Spherical Coordinates

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DianaSagita
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Volume Integral! Help!

I need help with this:

Find volume of figure bounded with surface (x^2+y^2+z^2+1)^2=8*(x^2+y^2)

I tried Ostrogradsky, and spherical coordinate system with it, but I can't find boundaries...

PLEASE! HELP ME!
 
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Welcome to PF!

DianaSagita said:
I need help with this:

Find volume of figure bounded with surface (x^2+y^2+z^2+1)^2=8*(x^2+y^2)

I tried Ostrogradsky, and spherical coordinate system with it, but I can't find boundaries...

PLEASE! HELP ME!

Hi DianaSagita ! Welcome to PF! :smile:

(what's Ostrogradsky? :confused: )

(oh, have a squared: ²)

Hint: it's obviously cylindrically symmetric, so write x² + y² = r², to give:

(r² + z² + 1)² - 8r² = 0. :smile:
 
Thanks a lot. I did it! :)