A square sheet of cardboard 10 on a side is made into an ope

Solution

Let us assume that the squares cut are x cm by x cm. The dimensions of the box will then be: l = 10 - 2x, w = 10 - 2x and h = x => Volume is x(10- 2x)² = 100x - 20x² + 4x³ dV/dx = 100x - 20x² + 4x³ = 0......at maximum => x² - 5x + 20 = 0