Double Integration to Find Volume

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Homework Statement



Find the volume of the region inside the surface z=x^2+y^2 and between z=0 and z=10

Homework Equations



x^2+y^2=10

The Attempt at a Solution



I know that I have to use some sort of double integration to find this volume, but I'm not really sure where to begin with the problem
 
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\iiint_V dV the upper curve is z=10 the lower curve is z=0 the area of integration in \mathbb{R}^2 is a circle of radius 10. Now use cyclindrical change of variable.
 
hmm...I may try that if I can't find an alternative, but is there any way to do this problem with a double integration and not a triple integration? because the section I'm working with is strictly double integration
 
That's a paraboloid. Since you have "flat" bottom and top I recommend you imagine the solid consisting of thin horizontal pieces. It should be obvious that the piece at height z is a disk satisfying x^2+ y^2= z. What is the area of that disk? If you think of the disk as having thickness "dz", what is its volume? Now "add" the volumes of all those disks.
 
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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