$\frac{\log \sqrt{8}}{\log 8}$ is equal to
Aptitude
Logarithm
Difficulty: Easy
Choose an option
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A$\frac{1}{\sqrt{8}}$
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B$\frac{1}{4}$
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C$\frac{1}{2}$
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D$\frac{1}{8}$
Answer
Correct Answer: $\frac{1}{2}$
Explanation
Concept & Formula
This problem tests your knowledge of the power rule of logarithms, which allows you to move an exponent from the argument to the front of the logarithm as a coefficient.
$$\log (a^n) = n \log a$$
You also need to convert a square root into a fractional exponent: $\sqrt{x} = x^{\frac{1}{2}}$.
Step-by-Step Solution
* **Given:** $\frac{\log \sqrt{8}}{\log 8}$
* **Convert radical to exponent:** Express $\sqrt{8}$ in the numerator as a fractional power.
$$\sqrt{8} = 8^{\frac{1}{2}}$$
* **Substitute this back into the expression:**
$$\frac{\log (8^{\frac{1}{2}})}{\log 8}$$
* **Apply the power rule:** Move the exponent $\frac{1}{2}$ to the front of the logarithm in the numerator.
$$\frac{\frac{1}{2} \log 8}{\log 8}$$
* **Simplify the fraction:** The term $\log 8$ appears in both the numerator and denominator, so they cancel out perfectly.
$$\frac{1}{2}$$
Exam Strategy & Shortcut
Whenever you see a logarithm of a root divided by a logarithm of the same base number, the answer is simply the fractional exponent of the root. $\sqrt{x}$ is the $\frac{1}{2}$ power, so the ratio is immediately $\frac{1}{2}$. You can bypass all intermediate written steps.
Common Pitfall
A major error is incorrectly simplifying the fraction by "canceling" the log terms improperly, or mistakenly trying to divide the arguments like $\frac{\sqrt{8}}{8}$. Logarithms do not work like linear algebraic variables; you must apply log properties before simplifying.
Final Answer
**Therefore, the correct answer is $\frac{1}{2}$.**