find global min/max: f(x,y)= x^3-2y ; 0<=x, y<=1 3. The attempt at a solution - I know that the critical points don't work since there are none, but what I'm not understanding is how to draw the square from 0<=x, y<=1. The solutions has the points (0,0), (1,0), (1,1), (0,1), but I'm not sure how you determine that. I guess what is getting me is why x is limited at 1 for the square. I understand how to work the problem except for this part. Please help.