Let
be the side of the square ends and
be the length of the package.
The volume of the rectangular box is
.
Find the volume function in terms of
.
Grith + Length
.
.


.
.
Differentiate on each side with respect to
.

Find the critical numbers by equating derivative to zero.
\


.
Substitute
in
.


.



is maximum when
and
.
The dimensions are
and
.