Use double integral to find the volume

zhuyilun
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Homework Statement


bounded by x^2+y^2=r^2 and y^2 +z^2=r^2
i guess r is just a random constant


Homework Equations





The Attempt at a Solution


i don't even have a clue of how to start this question
 
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I have posted a "freehand" picture to get you started. The picture shows the intersection of the cylinders in the first octant so it represents 1/8th of the volume. You will want to use a yz integral. I have oriented it so to make it "easier" to see.

forumcylinders.jpg


[EDIT] Corrected mis-labeling of axes, use an xz integral
 
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Actually that illustration is for x2+y2=r2 and x2+z2=r2.

Not a huge deal though, since it gives the same numerical answer either way. Just rotate the axis labels one place in the clockwise direction and use an xz integral.
 
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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