Multiple integral change of variables

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SUMMARY

The discussion focuses on computing the integral of the function x*e^y over a specified region R in the uv-plane, defined by the transformations u=x^2 + y^2 and v=x^2 + y^2 - 2y. The region R is bounded by the circles x^2 + y^2 = 1 and x^2 + y^2 = 2y, specifically in the first quadrant. The initial limits of integration proposed were 0 <= u <= 1 and 0 <= v <= u, which were questioned for accuracy. Participants suggested completing the square for the second condition and solving for y in terms of u and v, emphasizing the relationship u-v.

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BrownianMan
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Let R denote the region inside x^2 + y^2 = 1 but outside x^2 + y^2 = 2y with x=>0 and y=>0. Let u=x^2 + y^2 and v=x^2 + y^2 -2y. Compute the integral of x*e^y over the region D in the uv-plane which corresponds to R under the specified change of coordinates.

I'm having trouble with this one. My first attempt at figuring out the new limits of integration yielded 0<=u<=1 and 0<=v<=u, which seems wrong to me. I'm also not sure how to change the integrand to make it a function of u and v.
 
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I'm still trying to work out the new limits of integration myself, but I think it might help to complete the square for the second condition...

As for changing the function's variables, can you solve for y in terms of u and v? (Hint: What is u-v?)
 

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