## Deathfish 3 years ago How to Reverse order of integration. Double integral of (x+2y) Region is : y=1+x^2 to y=2x^2, x=0, x=1, dy dx edit : Question explicitly states reverse order of integration. I graphed out the region of integration... tried out the obvious x=(y-1)^(1/2) to x=(y/2)^(1/2) and y=0 to y=2, dxdy, but i got a complex number from square root of -1 ... from (0-1)^(1/2) ... so i tried out various other combinations such as x=0 to x=(y/2)^(1/2) and y=0 to y=1+x^2 ... and worked them out one by one to see if the answer matches the original using an online calculator (save time)... all don't return the same answer. think main problem i have is choosing 4 boundaries when the region graphed has only three surfaces.

1. upasnarayan

to reverse the order of integration, you just switch the limits on the integral to match dx or dy

2. upasnarayan

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3. Deathfish

edited question with more details on the problem im having

4. Deathfish

sorry can't read the drawing its a bit messy

5. upasnarayan

i can redo the drawing but the general idea for reversing the integration is to reverse the limits and reverse dx and dy... i think you're making it a bit too complicated

6. upasnarayan

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