How to Find the Volume of a Bounded Region with Sphere and Cone Equations

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Homework Statement



Find the volume of a region bounded above by the unit sphere x^2+y^2+z^2=1 and below by the cone z=sqrt(x^2+y^2). I am really confuse here.. ><


Homework Equations


Sphere: x^2+y^2+z^2=1
Cone: z=sqrt(x^2+y^2)

The Attempt at a Solution


I had plot the graph of the sphere and cone and i am pretty confuse to use. Just want to have some help.
 
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Volume requires a triple integral. How would you set this up? have you ever used polar/cylindrical/spherical coordinates?
 
Tea, i try using polar coordinates..

In the spherical, the equation of the sphere is r = 1

And the cone is rcosθ=√(r^2 sin^2 θ cos^2 φ + r^2 sin^2 θ sin^2 φ)=rsinθ

If we divide both sides by rcosθ, then we get

tanθ=1,θ=π/4

So, we have the triple integral:

∫0-2pi ∫0-(π/4) ∫0-1 (r^2 sinθdrdθdφ)

I am not sure if this is correct..
 
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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