
Bobosharif S. answered 11/12/20
PhD in Math, MS's in Calulus
∫∫Rxydxdy, where R={y=1/2x, y=3/2x, xy=1/2, and xy=3/2},
First I'm not sure if it is y=(1/2) x or y=1/(2x). The same with y=3/2x,,
I think it should be y=(1/2) x and y=(3/2)x
You can draw, to see how looks the region R. Then make substitution xy=u/v and y=v and find the Jacobian of transformation form (x,y) to (u,v) and define new region. Then evaluate double integral w.r. to u and v.
To find Jacobian, you have to express x and y as functions of u and v, that is x=x(u,v), y=y(u,v):
x=u/v2, y=v. Remember how to find Jacobian dxdy=|J| dudv, J={{dx/du,dx/dv},{dy/du,dy/dv}} <-- this a matrix.
Continue, if it is still hard, let me know, I can provide more assistance.