Use properties of logarithms to expand each logarithmic expression as much as possible. Where possible, evaluate logarithmic expressions without using a calculator. $\log_{4} (\frac{\sqrt{x}}{64})$

검증된 단계별 안내

Recall the logarithmic property for quotients: $\log_b \left( \frac{M}{N} \right) = \log_b M - \log_b N$. Apply this to rewrite $\log_4 \left( \frac{\sqrt{x}}{64} \right)$ as $\log_4 (\sqrt{x}) - \log_4 (64)$.

Express the square root as an exponent: $\sqrt{x} = x^{\frac{1}{2}}$. Use the power rule of logarithms: $\log_b (M^p) = p \log_b M$. So, $\log_4 (\sqrt{x}) = \log_4 (x^{\frac{1}{2}}) = \frac{1}{2} \log_4 x$.

Rewrite 64 as a power of 4 if possible. Since $4^3 = 64$, we have $64 = 4^3$. Use the power rule again: $\log_4 (64) = \log_4 (4^3) = 3 \log_4 4$.

Recall that $\log_b b = 1$ for any base $b$. Therefore, $\log_4 4 = 1$, so $\log_4 (64) = 3 \times 1 = 3$.

Combine all parts to write the expanded form: $\log_4 \left( \frac{\sqrt{x}}{64} \right) = \frac{1}{2} \log_4 x - 3$.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Properties of Logarithms

Properties of logarithms include rules such as the product, quotient, and power rules. These allow us to rewrite logarithmic expressions by expanding or condensing them. For example, log_b(M/N) = log_b(M) - log_b(N) and log_b(M^k) = k * log_b(M). These properties are essential for simplifying and expanding logarithmic expressions.

Radicals and Exponents

Understanding how to express radicals as fractional exponents is crucial. For instance, the square root of x can be written as x^(1/2). This conversion allows the use of logarithm power rules to simplify expressions involving roots. Recognizing this helps in expanding logarithmic expressions involving radicals.

Change of Base and Evaluating Logarithms

Evaluating logarithms without a calculator often involves expressing numbers as powers of the base. For example, 64 can be written as 4^3 since 4^3 = 64. This allows direct simplification of logarithmic terms like log_4(64) = 3. This concept helps in simplifying and evaluating logarithmic expressions exactly.

Use properties of logarithms to expand each logarithmic expression as much as possible. Where possible, evaluate logarithmic expressions without using a calculator. log4(x64)\(\log\)_4\(\left\)(\(\frac{\sqrt{x}\)}{64}\(\right\))