Find the triple integral of xy

magnifik
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find the triple integral of xy where E is bounded by y = x^2 and x = y^2 and the planes z = 0 and z = x + y.

i got 1/3 as a solution, but I'm not sure if i did it right, specifically the part in finding the boundaries for x and y. i found that they intersected at (0,0) and (1,1) so i had the region
[0,1] x [0,1] x [0,x+y] then evaluated the triple integral dzdydx. did i take the right approach?
 
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Your limits for the second integral are incorrect. If your outside integral is with respect to x, the limits of the middle integral should be the upper and lower limits of y for a constant value of x.
 
vela said:
Your limits for the second integral are incorrect. If your outside integral is with respect to x, the limits of the middle integral should be the upper and lower limits of y for a constant value of x.

is the boundary 0 to x^2?
 
No. Graph the functions on the xy-plane.
 
since it's only in the first quadrant the lower bound should be x^2 and upper bound should be sqrt(x)?
 
Yup, that's right.
 
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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