I am facing another problem that I can't compute the extremes forDoh)
f(xy)=e^{x}(x^{2}-y^{2})
so far I have:
fx= 2xe^{x }+ e^{x}(x^{2}-y^{2})
fy= -2ye^{x }fxx=2e^{x}+2xe^{x} + e^{x}(x^{2}-y^{2}) + 2xe^{x }
fyy= -2e^{x }fxy= -2ye^{x How do I find the extremes? I set fx and fy to 0, but I can't solve for x and y. Thanks for any help.}