Triple Integral with Spherical Coordinates

veritaserum
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Homework Statement


Evaluate \int\int\int 1/\sqrt{x^{2}+y^{2}+z^{2}+3} over boundary B, where B is the ball of radius 2 centered at the origin.


Homework Equations


Using spherical coordinates:
x=psin\Phicos\Theta
y=psin\Phisin\Theta
z=pcos\Phi

Integral limits:
dp - [0,2]
d\Phi - [0,\pi]
d\Theta - [0,2\pi]

The Attempt at a Solution


I am just having trouble finding a good substitution for the integrand. When I substitute x,y, and z with the spherical substitutions, I just get a huge jumbled mess that I can't make any sense of.
 
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whoops sorry, the integrand should be
\frac{dV}{\sqrt{x^{2}+y^{2}+z^{2}+3}}
 
veritaserum said:
When I substitute x,y, and z with the spherical substitutions, I just get a huge jumbled mess that I can't make any sense of.

Show us. And keep in mind that \sin^2\eta+\cos^2\eta=1.
 
lol even trying to type that out is a huge jumbled mess in itself. i understand the property you gave me, it's just that i am not able to factor out enough terms such that i leave that identity intact.
 
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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