How do you evaluate the integration of integration of cos (x^2+y^2) dx dy?
Hello Anna,
For this question, it is handy to convert to polar coordinates.
Recall that,
r^{2} = x^{2} + y^{2}, x = r cosθ, y= r sinθ.
And that dx dy changes into r dr dθ.
Without knowing more about the region of integration, this is about all the help that can be given.
Hope this helps,
Tyler
Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.