Find the volume. Triple integral.

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Find volume of common part of sphere and cylinder.

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My try in cylndrical coordinates: $$\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}}\int_{0}^{Rcos\phi}\int_{-\sqrt{R^2-r^2}}^{\sqrt{R^2-r^2}}1r dzdr d\phi =$$
$$ =2\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}}\int_{0}^{Rcos\phi} \sqrt{R^2-r^2}rdr d\phi$$

Is it correct? What is the triple integral in spherical coordinates?

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Looks like you have correct set up for cylindrical coordinates.

When you integrate remember that $\sqrt{R^2 - R^2\cos^2\theta} = R|\sin\theta|$

In spherical:

$x = \rho\cos\theta\cos \phi\\ y = \rho\cos\theta\cos \phi\\ z = \rho\sin \phi$

you will have to break it up into two integrals.

For one integral $\rho$ will have the freedom to move from $0$ to $R$

But we need to find limits for $\phi$

Lets find the contour where the cylinder meets the sphere

$(x,y,z) = (R\cos^2\theta, R\cos\theta\sin\theta, R\sin\theta)$

$\phi = \theta$

$2\int_{-\frac{\pi}{2}}^\frac{\pi}{2}\int_\theta^\frac{\pi}{2}\int_0^R \rho^2\sin\phi\ d\rho\ d\phi\ d\theta$

Since the region is symmetric across they xy plane, I am integrating half the region and doubling it.

Now we need the integral where $\rho$ is limited by the cylinder wall.

plugging the polar expressions into

$x^2 + y^2 - Rx = 0$ we get

$\rho^2\cos^2\phi - R\rho\cos\theta\cos\phi = 0\\ \rho = R\cos\theta\sec\phi$

$2\int_{-\frac{\pi}{2}}^\frac{\pi}{2}\int_0^\theta\int_0^{R\cos\theta\sec\phi} \rho^2\sin\phi\ d\rho\ d\phi\ d\theta $