This is not homework, but it is in my book and I find it hard to solve:
Determine the points where $f$ is has a local minimum/maximum. Determine if it strong/weak and absolute/relative and interior extremum or boundary extremum.
$$f(x,y)= (x^2-y^2)e^{-x^2-y^2}$$ The domain of $f$ is $E=\{(x,y): x^2+y^2 \leq 4 \}$
A worked solution would be really appreciated. Or if someone knows some worked solutions of exercises like these (somewhere on the internet), that would be great as well. Or a step-by-step plan how to solve exercises like these. In other words, any help is really appreciated.