The product of two numbers is
.
Let the two numbers are
and
.
The second number is reciprocal of first number.
\Therefore,
.
The sum of first number and the second number is minimum.
\Consider the sum function as
.
Thus,
.
Apply derivative on each side with respect to
.

Find the critical numbers by equating derivative to zero.
\


.
The first number is
.
The second number is
.


is minimum when
.
The two numbers are
and
.
The two numbers are
and
.