Which of the following is the simplified form of [tex]\sqrt[7]{x} \cdot 7^7 \cdot \sqrt[7]{x}[/tex]?

A. [tex]x^{\frac{3}{7}}[/tex]
B. [tex]x^{\frac{1}{7}}[/tex]
C. [tex]x^{\frac{3}{21}}[/tex]
D. [tex]21 \sqrt{x}[/tex]



Answer :

To simplify the expression [tex]\(\sqrt[7]{x} \cdot 7^7 \cdot \sqrt[7]{x}\)[/tex], let's go through the process step-by-step:

1. Convert the roots to exponents:
[tex]\(\sqrt[7]{x}\)[/tex] can be rewritten as [tex]\(x^{\frac{1}{7}}\)[/tex]. Therefore, the expression becomes:
[tex]\[ x^{\frac{1}{7}} \cdot 7^7 \cdot x^{\frac{1}{7}} \][/tex]

2. Combine like terms:
Notice that [tex]\(x^{\frac{1}{7}} \cdot x^{\frac{1}{7}}\)[/tex] can be combined using the property of exponents which states that when multiplying like bases, you add the exponents:
[tex]\[ x^{\frac{1}{7}} \cdot x^{\frac{1}{7}} = x^{\frac{1}{7} + \frac{1}{7}} = x^{\frac{2}{7}} \][/tex]

3. Multiply the components:
So now, the expression simplifies to:
[tex]\[ x^{\frac{2}{7}} \cdot 7^7 \][/tex]

4. Simplifying the result:
This expression involves an exponential of 7 and another component with a fractional exponent. We note that [tex]\(7^7\)[/tex] is a constant (which equals 823543).
Thus our expression becomes:
[tex]\[ 823543 \cdot x^{\frac{2}{7}} \][/tex]

Therefore, the simplified form of [tex]\(\sqrt[7]{x} \cdot 7^7 \cdot \sqrt[7]{x}\)[/tex] is:
[tex]\[ 823543 \cdot x^{\frac{2}{7}} \][/tex]

Comparing this with the provided choices, none of them exactly match this form. However, the closest simplified form in the choices is:

[tex]\[ \boxed{x^{\frac{2}{7}}} \][/tex]

Given it doesn't directly match any choices, we treat the computed [tex]\(823543 \cdot x^{\frac{2}{7}}\)[/tex] as the most accurate description.