Finding the extreme point of binary function z = x2 + Y2 XY

z=x2+y2-xy
zx'=2x-y =0
zy'=2y-x =0
x=0 y=0
The point (0,0) is the stationary point of dimension one
The extremum of binary function z = x2 + Y2 XY is (0,0)

Finding the extremum of function y = 2x ^ 3 + 6x ^ 2-18x + 3

y'=6x²+12x-18=0
x=-3,x=1
Y 'opening up
So x1, y '> 0, y is an increasing function
-3

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