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**math951** double integral 2yDA, where R is the region in the first quadrant bounded above by the circle (x-1)^2+y^2=1

and below by the line y=x

So we know the top limit is going to be the circle, and the bottom limit is going to be the line y=x.

We know that the circle has a radius of 1, and the center is (1,)

I have to evaluate in this in polar coordinates, so 2y turns into 2r^2sin(thetta) drd(thetta)

I just do not know how to find the limits for this, I am able to graph it and see it visually, but I cannot find the limits, nor do I understand why they are.

I guess I can see how thetta starts at pi/4 because of y=x, but how the hell does it end at pi/2???

I think for the dr limits I understand it. Please someone correct me if I am wrong. They found the bottom limit as 0 from y=x, and we are given y=0. then they found the top limit, from (x-1)^2+y^2=1 by converting this into polar coordinates??