posted by KC .
A box with an open top is to be constructed from a rectangular piece of cardboard with dimensions 12 in by 12 in by cutting out equal squares of side x at each corner and then folding up the sides as in the figure. Express the volume V of the box as a function of x.
after cutting two tabs out, the sides are 12-2x
v(x) = x(12-2x)^2