Green's theorem question

1. Apr 1, 2006

denian

http://www.mrnerdy.com/forum_img/whichcorrect2.JPG [Broken]

which one is correct?
[PLAIN]http://www.mrnerdy.com/forum_img/whichcorrect.JPG [Broken]

i tried both, and both gives different answer.
one is 19/20 and another is 7/60

Last edited by a moderator: May 2, 2017
2. Apr 1, 2006

Galileo

In the upper integral, you should go from $-\sqrt{x}$ to $-x$. The other one is correct. Both integrals have the value -7/60. The integrand is negative in the region over which you're integrating ($y\in [0,1]$) so the answer should be negative. Lots of chances to mess up with minus signs here, so be careful....

3. Apr 4, 2006

denian

thank you very much, galileo