Question

Maths help please!!!!!!!!!!!

Answer 1

Answer:

Step-by-step explanation:

Remark

Assume all of the sheet of plywood is to be used.

Front and back = 2 * 2x *h

Top and Bottom = 2 * 2x * x

Left/Right side = 2 * x * h

Total area = 4xh + 4x^2 + 2xh

Total area = 6xh + 4x^2

Total area = 600

6xh + 4x^2 = 600

h = (600 - 4x^2)/6x

h = 100/x - 2/3 x

Volume = x * 2x * h

Volume = 2x^2 * (100/x - 2/3 x)

Volume = 200x - 4/3  x^3

I can do this without calculus (I think), but it is much easier to use it.

dV/dx = 200 - 4x^2

This is a maximum when dV/dx = 0

dV/dx = 200 - 4x^2 = 0

4x^2 = 200

x^2 = 50

x = 5√2