Suppose thathas continuous second partial derivatives in a neighbourhood of and thatat
DefineatForm the discriminantIfthenis a saddle point.
Ifthenhas a local minimum at
Ifand a local maximum atif
Suppose thathas continuous second partial derivatives in a neighbourhood of and thatat
DefineatForm the discriminantIfthenis a saddle point.
Ifthenhas a local minimum at
Ifand a local maximum atif