Confused on what u do next with an exact equation, Diff EQ

[mr_coffee]

Hello everyone. We just started working with exact equations and I'm confused on what I do next! here is the problem:
Use the "mixed partials" check to see if the following differential equation is exact.
If it is exact find a function F(x,y) whose level curves are solutions to the differential equation
http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/71/5a4f0007c2fd2947228eee9825b55d1.png
http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/8d/8616ca1dd6ce230911485b98a57fa31.png

Here is my work, I submitted:
2*y^2+2*x^2-4 which was wrong.

WOrk:
http://img206.imageshack.us/img206/6632/lastscan3tp.jpg

Thanks!

 

[mathmike]

your int of 2xy^2 + 4y is incorrect

 

[HallsofIvy]

And what, again, is $\int (2xy^2+ 4y)dx$?

Did you forget that you were integrating, not differentiating?

 

[mr_coffee]

Thanks everyone! yeah I don't know what i was thinking! I got:
http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/8d/8616ca1dd6ce230911485b98a57fa31.png http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/8b/ad397009ac98a90c5581831292c16e1.png
Which is right! weee!