Hi,

Currently doing a problem with max/min problems and Maximizing the volume.

A sheet of cardboard 30cm by 40cm is to be cut into a box with a lid. The box shape is one of a rectangular cereal box.

I have worked the total area to be:

120cm^2 = 2zy + 2xy + 2xz

But im now stuck on what to do?

I need to find the dimensions that will maximise the volume and prove that its a maximum.