Answer:
18" X 18" X 36"
Step-by-step explanation:
Given a square base container of height h, let a side of the base =s
The volume of the container, [tex]V= s^2h[/tex]
If the sum of its height and girth (the perimeter of its base) equals 108 in
[tex]4s+h = 108\\h = 108-4s[/tex]
Substituting h=108-4s into V
[tex]V= s^2(108-4s)[/tex]
We are required to determine the maximum volume of such container, first we take the derivative:
[tex]V'(s)= s(216-12s)[/tex]
Optimizing:
[tex]s(216-12s)=0\\216-12s=0\\12s=216\\s=216 \div 12\\s=18[/tex]
Recall that: h = 108-4s
[tex]h = 108-4(18)=108-72=36inch[/tex]
The dimensions of the carton are 18" X 18" X 36".