How do you minimize and maximize f(x,y)=x-y/(x-y/(x-y))f(x,y)=xyxyxy constrained to 1<yx^2+xy^2<161<yx2+xy2<16?

1 Answer
Feb 20, 2017

See below.

Explanation:

This problem can be successfully handled with the Lagrange Multipliers technique.

The local maxima/minima points are

((f(x,y),x,y, "type"), (-0.750704,-1.71756,1.25284,"maximum"), (1.81974,0.562693,-1.64382,"minimum"), (-3.39363,-4.05723,2.44297,"maximum"), (3.33301,1.4188,-4.14166,"minimum"))

Attached a plot showing the feasible region superimposed to the objective function level curves, with the local maxima/minima points.

enter image source here