High School

What is the cube root of [tex]8x^{27}[/tex]?

A. [tex]2x^3[/tex]
B. [tex]2x^9[/tex]
C. [tex]4x^3[/tex]
D. [tex]4x^9[/tex]

Answer :

To find the cube root of the expression

[tex]$$
8x^{27},
$$[/tex]

we can use the property that the cube root of a product is equal to the product of the cube roots. That is,

[tex]$$
\sqrt[3]{ab} = \sqrt[3]{a} \cdot \sqrt[3]{b}.
$$[/tex]

1. First, separate the given expression into two parts:

[tex]$$
\sqrt[3]{8x^{27}} = \sqrt[3]{8} \cdot \sqrt[3]{x^{27}}.
$$[/tex]

2. Compute the cube root of the numerical part:

[tex]$$
\sqrt[3]{8} = 2 \quad \text{since} \quad 2^3 = 8.
$$[/tex]

3. Next, compute the cube root of the variable part by using the rule of exponents for radicals:

[tex]$$
\sqrt[3]{x^{27}} = x^{27/3} = x^9.
$$[/tex]

4. Combine the two results to obtain the final answer:

[tex]$$
\sqrt[3]{8x^{27}} = 2 \cdot x^9 = 2x^9.
$$[/tex]

Thus, the cube root of [tex]$8x^{27}$[/tex] is

[tex]$$
\boxed{2x^9}.
$$[/tex]