The volume of a shape is the amount of space in it.
- The function that models the volume is [tex]V(x) = 2x\cdot (11 - 2x)\cdot (8 - 2x)[/tex].
- The reasonable domain is: (0, 4) u (4, 5.5)
- The x-intercepts are the points where the paper is still flat
- The lengths of the square that maximizes the volume of the box are 1.5 and 4.8
When the length and width of the paper is decreased, the dimension of the prism becomes
[tex]Length = 11-2x[/tex]
[tex]Width = 8 - 2x[/tex]
[tex]Height = 2x[/tex]
(a) The function
The function that represents the volume is:
[tex]V(x) = Length \times Width \times Height[/tex]
So, we have:
[tex]V(x) = (11 - 2x) \times (8 - 2x) \times 2x[/tex]
Rewrite as:
[tex]V(x) = 2x\cdot (11 - 2x)\cdot (8 - 2x)[/tex]
(b) The graph and the domain
See attachment for the graph of [tex]V(x) = 2x\cdot (11 - 2x)\cdot (8 - 2x)[/tex]
From the graph, we have the x-intercepts to be 0, 4 and 5.5
At these points, the volume of the prism is 0.
So, the reasonable domain is: (0, 4) u (4, 5.5)
(c) The interpretation of the x-intercepts
The x-intercepts are the points where the paper is still flat (i.e. the prism has no height or no width or no length)
(d) Dimension that maximizes the volume
We have:
[tex]V(x) = 2x\cdot (11 - 2x)\cdot (8 - 2x)[/tex]
Expand
[tex]V(x) = 2x \cdot (88 - 22x - 16x + 4x^2)[/tex]
[tex]V(x) = 2x \cdot (88 -38x + 4x^2)[/tex]
Open bracket
[tex]V(x) = 176x -76x^2 + 8x^3[/tex]
Differentiate
[tex]V'(x) = 176 -152x + 24x^2[/tex]
Set to 0
[tex]176 -152x + 24x^2=0[/tex]
Rewrite as:
[tex]24x^2 -152x + 176=0[/tex]
Divide through by 8
[tex]3x^2 -19x +22 =0[/tex]
Using a graphing calculator, the value of x is approximately:
[tex]x = 1.5[/tex] and [tex]x = 4.8[/tex]
Hence, the lengths of the square that maximizes the volume of the box are 1.5 and 4.8
Read more about volumes at:
https://brainly.com/question/1578538