Use the change-of-base theorem to find the logarithm.

[tex]\[
\log_4 5
\][/tex]

[tex]\[
\log_4 5 = \square
\][/tex]

(Simplify your answer. Do not round until the final answer.)



Answer :

Sure, let's find [tex]\(\log_4(5)\)[/tex] using the change-of-base theorem.

The change-of-base theorem states that for any positive numbers [tex]\(a\)[/tex], [tex]\(b\)[/tex], and [tex]\(c\)[/tex] where [tex]\( b \neq 1 \)[/tex] and [tex]\( c \neq 1 \)[/tex]:
[tex]\[ \log_b(a) = \frac{\log_c(a)}{\log_c(b)} \][/tex]

In this problem, we're looking to find [tex]\(\log_4(5)\)[/tex]. We can choose any base [tex]\(c\)[/tex] for our logarithms, but it’s common to use the base 10 (common logarithm) or base [tex]\(e\)[/tex] (natural logarithm). Here, we'll use base 10.

Applying the change-of-base theorem:
[tex]\[ \log_4(5) = \frac{\log_{10}(5)}{\log_{10}(4)} \][/tex]

Now, we need to find the values of [tex]\(\log_{10}(5)\)[/tex] and [tex]\(\log_{10}(4)\)[/tex].

By calculation:
[tex]\[ \log_{10}(5) \approx 0.6989700043360187 \][/tex]
[tex]\[ \log_{10}(4) \approx 0.6020599913279623 \][/tex]

So, substituting these values into the formula:
[tex]\[ \log_4(5) = \frac{0.6989700043360187}{0.6020599913279623} \approx 1.1609640474436813 \][/tex]

Therefore, [tex]\(\log_4(5) \approx 1.1609640474436813\)[/tex].