Open-box Problem. An open-box (top open) is made from a rectangular material of dimensions
a=8
inches by
b=7
inches by cutting a square of side
x
at each corner and turning up the sides (see the figure). Determine the value of
x
that results in a box the maximum volume. Following the steps to solve the problem. Check Show Answer only after you have tried hard. (1) Express the volume
V
as a function of
x:V=
(2) Determine the domain of the function
V
of
x
(in interval form): (3) Expand the function
V
for easier differentiation:
V=
(4) Find the derivative of the function
V:V^(')=
(5) Find the critical point(s) in the domain of
V
: (6) The value of
V
at the left endpoint is (7) The value of
V
at the right endpoint is (8) The maximum volume is
V=
(9) Answer the original question. The value of
x
that maximizes the volume is: