A box with a square base and open top must have a volume of 119164 cm. We wish to find the dimensions of the box that minimize the amount of material used. First, find a formula for the surface area of the box in terms of only x, the length of one side of the square base. [Hint: use the volume formula to express the height of the box in terms of x.] Simplify your formula as much as possible. A(x) Next, find the derivative, A'(x). A'(x) Now, calculate when the derivative equals zero, that is, when A'(x) = 0. [Hint: multiply both sides by x.] A'(x) = 0 when x