\
Step 1:
\Method of Lagrange Multipliers :
\If f and g satisfy the hypothesis of Lagranges theorem, and let f have a minimum or maximum subject to the constraint
. To find the minimum or maximum of f use these steps.
1. Simultaneously solve the equations
and
by solving the following system of equations.

2. Evaluate f at each solution point obtained in the first step. The greatest valueyields the maximum of subject to the constraint
, and the least value yields the minimum of subject to the constraint
.
Step 2 :
\The function is
.
The constraint is
.
Consider 
Find the gradient
:

Find the gradient
:

Step 3 :
\Write the system of equations :
\
Solve equation (1) :
\
Substitute
equation (2).

Step 4 :
\Substitute
equation (3).

Substitute
equation (3).

Substitute
in the function
.

The maximum value of the function
is 2600.
Solution :
\The maximum value of the function
is 2600.
\