\
The function
,
.
Maximum value of a function exist either at the end points or at the critical points.
\First evaluate the function at the end points.
\Substitute
in
.

Substitute
in
.

\
Find the critical points.
\
is differentiable at all points because its a polynomial.
Therefore
are the only critical points.
Differentiate
on each sides with respect to
.

To find out critical points equate
to zero

and
and
.
and
and
.
and
and
.
and
and
.
Therefore the critical points are
,
and
.
\
Find the absolute maximum value.
\Substitute
in
.

.
Since
and
are positive numbers,
.
Absolute maximum is
.
\
Absolute maximum is
.