Question

(i)
A manufacturer wants to design an open box (without cover) having a square base and a
surface area of 108 m (dimension: x m long, x m width and h m tall). What dimension
will produce a box with maximum volume?
(ii)
Design a right circular cylinder oil can to carry 1 litre oil. The radius of the can is r and
its height is h. What dimension will use the least material?

Answer 1

x^2 +4xh = 108
x^2*h = V

Answer 2

Find V' =0