Evaluating a triple integral Spherical

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Homework Statement


z(x^2+y^2+z^2)^(-3/2) where x^2+y^2+z^2 ≤ 4 and z ≥ 1





The Attempt at a Solution


So spherically this comes down to cos∅sin∅dpdθd∅
p goes from 0 to 2, theta goes from 0 to 2pi, but I don't know how to figure out what ∅ goes from? I'm trying use trig identities but I'm getting the wrong answer, so maybe this don't work since the sphere is curved?
 
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Your limits for ##\rho## aren't correct. For example, consider the part of the z-axis which is inside the solid. It's only the part where 1 ≤ z ≤ 2. This would be inconsistent with ##\rho \le 1##, yet your lower limit for ##\rho## is 0.

In this case, you have cylindrical symmetry, so try drawing a cross section of the surface through, say, the xz plane. You should be able to see pretty easily the limits of ##\phi##, and you'll have to figure out the limits of ##\rho## as a function of ##\phi##.
 
Given the bounds, it might be easier to handle in cylindrical.
 
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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