Help with Changing of variables, Jacobian, Double Integrals?

Suy
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Homework Statement



Show that T(u,v) = (u2 - v2, 2uv)
maps to the triangle = {(u,v): 0 ≤ v ≤ u ≤ 4} to the domain D
bounded by x=0, y=0, and y2 = 1024 - 64x.

Use T to evaluate ∬D sqrt(x2+y2) dxdy

Homework Equations



The Attempt at a Solution



x=u2-v2
y=2uv
Jacobian= 4u2+4v2 dudv
I guess the equation in the changed variable integral should be ∫∫sqrt((u2-v2)2+(2uv)2) (4u2+4v2) dudv

But, I don't know how to get the bounds for the integrals in terms of u and v.
Can someone help me on this??
 
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The first part of the problem already told you what the bounds of u and v are
 
I know that 0 ≤ u ≤ 4 and 0 ≤ v ≤4.
For y^2 = 1024 - 64x, x is restricted from 0 ≤ x ≤16 and 0 ≤ y ≤32??
 
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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