Suppose $a\neq 0$. Compute $\log_{8a} b$ in terms of $a$ and $b$.
\($\log_{8a} b$ \)
Let this = x
In exponential form
(8a)^x = b take the log of both sides
log (8a)^x = log b and we can write
x * log (8a) = log b
x [ log 8 + log a ] = log b
x = [ log b ] / [ log 8 + log a ]