Homework Statement
Find critical points. f(x,y) = (x-1)^4 + (x-y)^4
The Attempt at a Solution
\frac{\partial f}{\partial x} = 4(x-1)^3 + 4(x-y)^3
\frac{\partial f}{\partial y} = - 4(x-y)^3
\frac{\partial f}{\partial x} = 0 ,
\frac{\partial f}{\partial y} = 0 ,
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