has
continuous second partial derivatives in a neighbourhood of
and that
at
University Maths Notes: Calculus – Maxima, Minima and Saddle Points – The Second Partials Test
Suppose thathas
continuous second partial derivatives in a neighbourhood of
and thatat
Define
at
Form
the discriminant
If
thenis
a saddle point.
If
then
has
a local minimum at
If
and
a local maximum at
if
