Moment of Inertia using Triple Integral

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Homework Statement


Compute the moment of inertia around the z-axis of the solid unit box [0,1]x[0,1]x[0,1] with density given by \delta=x^{2}+y^{2}+z^{2}.


Homework Equations


I=\int\int\intr^{2} \delta dV


The Attempt at a Solution


I know that the distance r^{2} from the z-axis would be x^{2}+y^{2}. I don't know how to determine the bounds and the order of the three integrals. Could someone please explain to me how to determine which order I should integrate, and then how I go about finding the bounds of integration for each of the three integrals.

Thanks!
 
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Since none of the boundaries on your volume is dependent on each other you can just write it as a simple 'volume' integral if you want to think of it that way, as if you're finding the volume of the cube but with the other terms involved: r^{2} and {\delta}

So in my mind it should be set up as follows:

\int_{0}^{1}\int_{0}^{1}\int_{0}^{1}(x^{2}+y^{2})(x^{2}+y^{2}+z^{2})dzdydx

The order of integration won't matter.
 
Oh, that's much easier than I was trying to make it. Thank 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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