Problem:The extrema of the function of two or more variable, Ctitical point, Lagrange Multipliers, Max-Min Existence Theorem.
Let f(x,y)=y2-2y-3yx2 . (a) Find the critical points of f(x,y). (b) Find the absolute maximum and minimum values of f on the closed and bounded set enclosed by x=√y , x=1andy=0.