Double integral transformation

vampireyal
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Homework Statement


evaluate the integral \int\int(x^4-y^4)e^{xy}dA

where R is the region bounded by xy=1, xy=2, x2-y2=1, and x2-y2=4


Homework Equations





The Attempt at a Solution



This is my first time on the forum, so forgive me if there are mistakes in this post. I am trying to find the transformation equations in order to convert the xy-plane equations to a uv-plane. Judging by the boundary equations, I let u=xy and v=x2-y2.

When I evaluate the xy equations using the transformation equations I get u=1, v=4, u=2, and v=1. which makes a square on the uv plane. I am not sure if I did this correctly though.

The next part of the problem asks to calculate the Jacobian, but I am not sure of how to calculate the partial derivatives based off my transformation equations. I can't seem to get x and y in terms of u and v, which makes me think that my transformation equations are wrong.

Any help is appreciated. Thank you.
 
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What is 'SUP' supposed to stand for exactly? I'm assuming it's a mistake when you typed your formula...
 
oh...that's funny that did that...it's just supposed to be superscripted...so int int (x^4-y^4)e^xy dA
 
Don't use "sup" inside LaTex. Use "^" instead.
 
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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