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Critical Point

EXPLORE THIS TOPIC IN the MathWorld Classroom

A function y=f(x) has critical points at all points x_0 where f^'(x_0)=0 or f(x) is not differentiable. A function z=f(x,y) has critical points where the gradient del f=0 or partialf/partialx or the partial derivative partialf/partialy is not defined.

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