Question 789015
An open rectangular box is to be made from a piece of cardboard 20 inches wide and 20 inches long by cutting a square from each corner and bending up the sides.
(a) Express the volume V of the box as a function of the size x of the cutout.
2
Volume  of box = x*(20-2x)(20-2x) cu.in

x((400 -80x+4x^2)=V

4x^3-80x^2+400x = V

(rectified)

*[illustration box.png]