Calculating Flux through a Sphere using Divergence Theorem

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Evaluate [URL]http://webwork.latech.edu/webwork2_files/tmp/equations/93/91cfe28c766cad38444f0213c651281.png[/URL] where [URL]http://webwork.latech.edu/webwork2_files/tmp/equations/59/a56001472f977192637ea927c607a61.png[/URL] and is the surface of the sphere of radius 6 centered at the origin.

Ok so I started by taking the divF to get 3y^2+3x^2+3z^2. Using polar coordinates I created the integral (from 0 to 2pi) of the integral (from 0 to pi/2) of the integral (from 0 to 6) (3r2sin2(theta)sin2(phi)+3r2cos2(theta)sin2(phi)+3r2cos2(phi)))r2sin(phi) d(phi)d(theta)d(r).

After all of that I simplified my answer down but I keep getting a huge number, 29314.82937, for an answer and it's incorrect. This problem seems very easy so I feel like I'm missing a very obvious step.
 
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If it helps, instead of converting each term, convert them as a group to r^2.
 
That is a good idea, but I still didn't come out with the right answer.
 
Why are you taking phi from 0 to pi/2? It should be to pi.
 
That is the million dollar question. Thank you very much my friend.
 
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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