CASE STUDY CHALLENGE
AOD: Optimizing the Golden Box
A man has an expensive square-shaped piece of golden board of side 36 cm. He wants to turn it into a box without a top by cutting a square from each corner and folding up the flaps.

Let \( x \) cm be the side of the square which is cut from each corner.
Answer the following questions:
| (i) | Find the expression for the volume (\( V \)) of the open box in terms of \( x \). | [1] |
| (ii) | Find the derivative \( \frac{dV}{dx} \). | [1] |
| (iii) |
(a) Find the value of \( x \) for which the volume (\( V \)) is maximum. — OR —
(b) Find the maximum volume of the open box. |
[2] |