Select the correct answer.

Which expression is equivalent to [tex]$7 x^2 \sqrt{2 x^4} \cdot 6 \sqrt{2 x^{12}}$[/tex], if [tex]$x \neq 0$[/tex]?

A. [tex][tex]$26 x^{22}$[/tex][/tex]
B. [tex]$13 x^{12} \sqrt{2}$[/tex]
C. [tex]$84 x^{10}$[/tex]
D. [tex]$42 x^{12} \sqrt{2}$[/tex]



Answer :

To simplify the expression [tex]\(7 x^2 \sqrt{2 x^4} \cdot 6 \sqrt{2 x^{12}}\)[/tex], we follow these steps:

1. Simplify inside the square roots:
- [tex]\(\sqrt{2 x^4}\)[/tex]:
- [tex]\(\sqrt{2 x^4} = \sqrt{2} \cdot \sqrt{x^4} = \sqrt{2} \cdot x^2\)[/tex]

- [tex]\(\sqrt{2 x^{12}}\)[/tex]:
- [tex]\(\sqrt{2 x^{12}} = \sqrt{2} \cdot \sqrt{x^{12}} = \sqrt{2} \cdot x^6\)[/tex]

2. Substitute back into the given expression:
- [tex]\(7 x^2 \sqrt{2 x^4} \cdot 6 \sqrt{2 x^{12}}\)[/tex]:
- [tex]\(7 x^2 (\sqrt{2} \cdot x^2) \cdot 6 (\sqrt{2} \cdot x^6)\)[/tex]
- [tex]\(7 x^2 (\sqrt{2} x^2) \cdot 6 (\sqrt{2} x^6)\)[/tex]

3. Combine and rearrange the constants, square roots, and like terms:
- Combine the constants:
- [tex]\(7 \cdot 6 = 42\)[/tex]

- Combine the square root terms:
- [tex]\(\sqrt{2} \cdot \sqrt{2} = 2\)[/tex]

- Combine the powers of [tex]\(x\)[/tex]:
- [tex]\(x^2 \cdot x^2 \cdot x^6 = x^{2+2+6} = x^{10}\)[/tex]

4. Put it all together:
- The expression becomes:
- [tex]\(42 \cdot 2 \cdot x^{10} = 84 x^{10}\)[/tex]

Thus, the equivalent expression is [tex]\(84 x^{10}\)[/tex].

The correct answer is:
[tex]\[ \boxed{84 x^{10}} \][/tex]