1. The problem statement, all variables and given/known data Let D be the region bounded by x=0, y=0, x+y=1, x+y=4. Using the change on variables x=u-uv, y=uv and the jacobian, evaluate the double integral double integral of dxdy/(x+y) 2. Relevant equations answer is 3 3. The attempt at a solution i drew the graph and found the boundaries x=1,y=0,x+y=1,x+y=4 and solved u and v for each boundary for x=0: 0=u-uv v=1 for y=0: 0=uv so either v=0 or v=0 or both u and v are 0 for x+y=1: u-uv+uv=1 u=1 for x+y=4: u-uv+uv=4 u=4 therefore i have the region in the uv plane [1,4]X[0,1] now dx=(1-v)du dy=udv therefore i get double integral(i-v)dvdu dudv with v varying from 0 to1 and u varying from 1 to 4 and i get 3/2? im not sure im doin the right method, i have a feeling im wrong when i let y=0 and assume v=0?