# How do you evaluate log_64 4?

$\frac{1}{3}$
Use${\log}_{b} a = \log \frac{a}{\log} b$.
Here, ${\log}_{64} 4 = \log \frac{4}{\log} 64 = \log \frac{4}{\log {4}^{3}} = \log \frac{4}{3 \log 4} = \frac{1}{3}$