Double Integrals over General Region

zm500
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Homework Statement



Find the Volume of the given solid
Bounded by the cylinders y^2+z^2=4 and x=2y, x=0,z=0 in the first octant

Homework Equations


double integral over a region D with f(x,y) dA

The Attempt at a Solution


I graphed it in a xyz plane and got these intervals
D = {(x,y)| 0\leqx\leq4;x/2\leqy\leq2}

where f(x,y) = \sqrt{}4-y^2 with respect to dydx

I don't know how to integrate this!
 
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You could try integrating in reverse order, if that would help. If not, just try a substitution, like y=2sin(u).
 
Thank You Very Much.
Reversing order did the trick.
 
Have a great day!
 
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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