Module 13 :  Maxima, Minima and Saddle Points, Constrained maxima and minima
Lecture 38 :  Second derivative test for local maxima / minima & saddle points [Section 38.1]
(ii)
On the other hand the function
 

has a local minimum at and

(iii)
The function
 

satisfies the property that Further, if we consider
the curve

Along this curve,

Thus, we can find points close to where
Similarly, along the curve

the function is given by

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