Volume using spherical coordinates

lap_tech
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Hello. Here is the problem I am currently having difficulties with:
"find the volume of the solid that lies inside the cone z^2 = 3x^2 + 3y^2 and between spheres x^2 + y^2 + z^2 = 1 and x^2 + y^2 + z^2 = 9"

I know that this integral needs to be setup in spherical coordinates... Here is the integral I came up with. I'm not sure if it is correct though...
v = integral from 1 to 3 integral from 0 to 2pie integral from pie/4 to pie/2
p^2 sin(phi) dp d(phi) d(theta)
does this seem correct?

let me try to put it in LaTeX format... (sorry if it dosen't work..)

V=\int_1^3 \int_0^\Pi \int_\frac{\pi}{4}^\frac{\pi}{2} \rho^2 \sin\phi dpd\phi d\theta
 
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Where do you get your angle values from??

When doing coordinate changes, it is always helpful to restate your equations in terms of your new coordinates.
First, the general transformation relations from Cartesian to polar:
x=r\sin\phi\cos\theta,y=r\sin\phi\sin\theta,z=r\cos\phi, 0\leq\theta\leq{2}\pi,0\leq\phi\leq\pi,0\leq{r}

Now, restatement of your equations delineating your region:
r^{2}=1, r^{2}=9,\tan^{2}\phi=\frac{1}{3}

What does this tell you?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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