Questions: Write the expression as a single logarithm.
log4(x^2-4) - 5 log4(x+2)
log4(x^2-4) - 5 log4(x+2) =
(Simplify your answer.)
Transcript text: Write the expression as a single logarithm.
\[
\begin{array}{c}
\log _{4}\left(x^{2}-4\right)-5 \log _{4}(x+2) \\
\log _{4}\left(x^{2}-4\right)-5 \log _{4}(x+2)=\square
\end{array}
\]
$\square$
(Simplify your answer.)
Solution
Solution Steps
To combine the given logarithmic expression into a single logarithm, we can use the properties of logarithms. Specifically, we will use the power rule, which states that \( a \log_b(c) = \log_b(c^a) \), and the quotient rule, which states that \( \log_b(m) - \log_b(n) = \log_b\left(\frac{m}{n}\right) \).
Apply the power rule to the term \( 5 \log_4(x+2) \).
Use the quotient rule to combine the two logarithmic terms into a single logarithm.
Step 1: Rewrite the Expression
We start with the expression:
\[
\log_{4}(x^{2}-4) - 5 \log_{4}(x+2)
\]
Using the power rule of logarithms, we can rewrite \(5 \log_{4}(x+2)\) as:
\[
\log_{4}((x+2)^{5})
\]
Thus, the expression becomes:
\[
\log_{4}(x^{2}-4) - \log_{4}((x+2)^{5})
\]
Step 2: Apply the Quotient Rule
Next, we apply the quotient rule of logarithms, which states that:
\[
\log_{b}(m) - \log_{b}(n) = \log_{b}\left(\frac{m}{n}\right)
\]
Applying this to our expression gives:
\[
\log_{4}\left(\frac{x^{2}-4}{(x+2)^{5}}\right)
\]
Step 3: Simplify the Expression
The expression can be further simplified. Noticing that \(x^{2}-4\) can be factored as \((x-2)(x+2)\), we rewrite the expression:
\[
\log_{4}\left(\frac{(x-2)(x+2)}{(x+2)^{5}}\right)
\]
This simplifies to:
\[
\log_{4}\left(\frac{x-2}{(x+2)^{4}}\right)
\]
Final Answer
Thus, the expression as a single logarithm is:
\[
\boxed{\log_{4}\left(\frac{x-2}{(x+2)^{4}}\right)}
\]