Jae is constructing an open box from a piece of cardboard that is 9 in. wide and 12 in. long. He cuts squares of equal size from each comer of
the cardboard, as shown in the picture, and then folds up the sides of the box. Write and simplify a polynomial function V for the volume of the box in terms of x

Respuesta :

Answer:

The polynomial function for the volume of the box ([tex]V[/tex]) in terms of [tex]x[/tex] is

[tex]V(x)= 108\cdot x -42\cdot x^{2}+4\cdot x^{3}[/tex].

Step-by-step explanation:

We present a representation of the specifications of the open box in a image attached below. The volume of the open box ([tex]V[/tex]), measured in cubic inches, is represented by this expression:

[tex]V = w\cdot h \cdot l[/tex]

Where:

[tex]w[/tex] - Width, measured in inches.

[tex]h[/tex] - Height, measured in inches.

[tex]l[/tex] - Length, measured in inches.

Polynomial functions in standard form are represented by the following form:

[tex]y = \Sigma_{i=0}^{n} c_{i}\cdot x^{i}[/tex]

Where:

[tex]n[/tex] - Order of the polynomial, dimensionless.

[tex]c_{i}[/tex] - i-th Coefficient, dimensionless.

[tex]x[/tex] - Indepedent variable, dimensionless.

[tex]y[/tex] - Dependent variable, dimensionless.  

If we get from figure that [tex]w = 12 - 2\cdot x[/tex], [tex]h = x[/tex] and [tex]l = 9 - 2\cdot x[/tex], then:

[tex]V = (12-2\cdot x) \cdot x \cdot (9-2\cdot x)[/tex]

[tex]V = (12\cdot x -2\cdot x^{2})\cdot (9-2\cdot x)[/tex]

[tex]V = 108\cdot x-18\cdot x^{2}-24\cdot x^{2}+4\cdot x^{3}[/tex]

[tex]V = 108\cdot x -42\cdot x^{2}+4\cdot x^{3}[/tex]

The polynomial function for the volume of the box ([tex]V[/tex]) in terms of [tex]x[/tex] is

[tex]V(x)= 108\cdot x -42\cdot x^{2}+4\cdot x^{3}[/tex].

Ver imagen xero099

The volume of a box is the amount of space the box can occupy.

The polynomial function is: [tex]\mathbf{V(x) = 4x^3 -42x^2 + 108x }[/tex]

The dimension of the cardboard is given as:

[tex]\mathbf{Length = 12}[/tex]

[tex]\mathbf{Width = 9}[/tex]

Assume the size removed from the box is x

The dimension of the box becomes

[tex]\mathbf{Length = 12 -2x}[/tex]

[tex]\mathbf{Width = 9 -2x}[/tex]

[tex]\mathbf{Height = x}[/tex]

So, the volume (V) of the box is:

[tex]\mathbf{V = Length \times Width \times Height}[/tex]

Substitute known values

[tex]\mathbf{V = (12 -2x) \times (9 - 2x) \times x}[/tex]

Open brackets

[tex]\mathbf{V = (12 -2x) \times (9x - 2x^2)}[/tex]

Open brackets

[tex]\mathbf{V = 108x -24x^2 - 18x^2 + 4x^3}[/tex]

[tex]\mathbf{V = 108x -42x^2 + 4x^3}[/tex]

Rewrite as:

[tex]\mathbf{V = 4x^3 -42x^2 + 108x }[/tex]

Express as a function

[tex]\mathbf{V(x) = 4x^3 -42x^2 + 108x }[/tex]

Hence, the polynomial function is:

[tex]\mathbf{V(x) = 4x^3 -42x^2 + 108x }[/tex]

Read more about volumes and functions at:

https://brainly.com/question/1758167