Solve the following:

[tex]\[ \sqrt{7} \times \sqrt[5]{7} \][/tex]

A. [tex]\(\frac{71}{10}\)[/tex]

B. [tex]\(76\)[/tex]

C. [tex]\(\frac{77}{10}\)[/tex]

D. [tex]\(\frac{1}{710}\)[/tex]



Answer :

To solve the expression [tex]\(\sqrt{7} \times \sqrt[5]{7}\)[/tex], we need to understand the properties of exponents and roots.

1. Convert roots to exponents:

The square root of a number [tex]\(a\)[/tex] can be written as [tex]\(a^{1/2}\)[/tex]. Similarly, the fifth root of [tex]\(a\)[/tex] can be written as [tex]\(a^{1/5}\)[/tex].

Therefore:
[tex]\[ \sqrt{7} = 7^{1/2} \][/tex]
and
[tex]\[ \sqrt[5]{7} = 7^{1/5} \][/tex]

2. Combine the exponents:

When multiplying two terms with the same base, we add the exponents. Hence:
[tex]\[ \sqrt{7} \times \sqrt[5]{7} = 7^{1/2} \times 7^{1/5} = 7^{1/2 + 1/5} \][/tex]

3. Find the common denominator and add the fractions:

The common denominator of 2 and 5 is 10. So, we convert the fractions:

[tex]\[ \frac{1}{2} = \frac{5}{10} \][/tex]
and
[tex]\[ \frac{1}{5} = \frac{2}{10} \][/tex]

Adding these fractions gives:
[tex]\[ \frac{5}{10} + \frac{2}{10} = \frac{7}{10} \][/tex]

4. Simplify the exponent:

So, the combined exponent is:
[tex]\[ 7^{1/2 + 1/5} = 7^{7/10} \][/tex]

5. Compute the value:

Knowing from the given information:
[tex]\[ 7^{7/10} \approx 3.9045287771227226 \][/tex]

We now check which option is closest to this value.

6. Compare with given options:

A) [tex]\(\frac{71}{10} = 7.1\)[/tex] [tex]\[ \text{(Not a close match)} \][/tex]
B) 76 [tex]\[ \text{(Not a close match)} \][/tex]
C) [tex]\(\frac{77}{10} = 7.7\)[/tex] [tex]\[ \text{(Not a close match)} \][/tex]
D) [tex]\(\frac{1}{710} \approx 0.0014\)[/tex] [tex]\[ \text{(Not a close match)} \][/tex]

Given these comparisons, it seems there is no exact choice that matches the calculated value. However, the closest computed value of [tex]\(7^{7/10}\)[/tex] does not directly correspond to any of the given multiple-choice options.