Square corners, with sidex cm, are cut from a square card with side 6 cm.
Then the edges are folded up to make a box.
Show that the volume of the box is V cm3 where V = 36x – 24x2 + 4x3.
much appreciated
The volume is calculated by:
$\displaystyle V = base\ area \cdot height$
With your values you get:
$\displaystyle base\ area = (6-2x)^2, 0\leq x \leq3$
$\displaystyle height = x$
Now plug in the terms into the formula of the volume, expand the brackets and collect like terms.