College

Find the volume of a rectangular prism if the length is [tex]4x[/tex], the width is [tex]2x[/tex], and the height is [tex]x^3 + 3x + 6[/tex].

Use the formula [tex]V = l \cdot w \cdot h[/tex], where [tex]l[/tex] is length, [tex]w[/tex] is width, and [tex]h[/tex] is height, to find the volume.

A. [tex]6x^5 + 18x^3 + 36x^2[/tex]
B. [tex]6x^6 + 18x^3 + 36x^2[/tex]
C. [tex]8x^5 + 24x^3 + 48x^2[/tex]
D. [tex]8x^6 + 24x^3 + 48x^2[/tex]

Answer :

To find the volume of a rectangular prism, we need to use the formula for volume:

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

where [tex]\( l \)[/tex] is the length, [tex]\( w \)[/tex] is the width, and [tex]\( h \)[/tex] is the height of the prism.

Given:

- Length ([tex]\( l \)[/tex]) = [tex]\( 4x \)[/tex]
- Width ([tex]\( w \)[/tex]) = [tex]\( 2x \)[/tex]
- Height ([tex]\( h \)[/tex]) = [tex]\( x^3 + 3x + 6 \)[/tex]

Let's find the volume:

1. Multiply the length and the width:

[tex]\[ l \cdot w = 4x \cdot 2x = 8x^2 \][/tex]

2. Now multiply the result by the height:

[tex]\[ V = 8x^2 \cdot (x^3 + 3x + 6) \][/tex]

We will distribute [tex]\( 8x^2 \)[/tex] to each term in the height expression:

- [tex]\( 8x^2 \cdot x^3 = 8x^{2+3} = 8x^5 \)[/tex]
- [tex]\( 8x^2 \cdot 3x = 24x^{2+1} = 24x^3 \)[/tex]
- [tex]\( 8x^2 \cdot 6 = 48x^2 \)[/tex]

3. Combine these results to get the expression for the volume:

[tex]\[ V = 8x^5 + 24x^3 + 48x^2 \][/tex]

Now let's match this expression to the given multiple-choice options:

- [tex]\( 6x^5+18x^3+36x^2 \)[/tex]
- [tex]\( 6x^6+18x^3+36x^2 \)[/tex]
- [tex]\( 8x^5+24x^3+48x^2 \)[/tex]
- [tex]\( 8x^6+24x^3+48x^2 \)[/tex]

The correct volume expression is:

[tex]\[ 8x^5 + 24x^3 + 48x^2 \][/tex]

Therefore, the correct answer is:

[tex]\( 8x^5 + 24x^3 + 48x^2 \)[/tex].