optimization: 4m wire cut into 2 pieces to form a square and circle

Question

A piece of wire 4 m long is cut into two pieces. One piece is bent into the shape of a circle of radius  and the other is bent into a square of side . How should the wire be cut so that the total area enclosed is: 

Answer 1

.....is maximized?

4 = 2πr + 4s

A = πr² + s²

Solve the first equation for one of the variables in terms of the other and substitute into the 2nd equation.

Then find the derivative of A with respect to the remaining variable and set the derivative = 0.

Solve for the variable.