Your limits are wrong
The integral is:
For the double integral over general region, the limits of the outer integral should be constants ..
I ahve the question , where and D is the region in the first quadrant D bounded by the curves and .
And i think im right in saying that this is the same as
but when i do the first integral it equals 0 so i dont know what to do with the next
oh i get it know i watched
YouTube - Calculating Double Integrals over General Regions
and i was just thinking about the limits wrong thanks