The function is
and
.
The linear function is
.
The quadratic function is
.

Apply derivative with respect to
.

Apply derivative with respect to
.


First derivative of
at
.

Second derivative of
at
.

The linear function is
.

The quadratic function is
.

Now plot the graphs of
,
and
.

From the graph the value of the
,
and
at
is same.
The approximations wrosen as we move away from
.
and
.

The value of the
,
and
at
is same.
The approximations wrosen as we move away from
.