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I am just learning logs, and can't get this one out ? How to prove that

$$ \log_a (b) \cdot \log_b (c) = \log_a (c) $$ in the format : log [base]([argument]) thank you .

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Try to translate into a statement about exponentials, by introducing new variables: $\log_a b= x$, so $a^x=b$, etc. –  Michael Weiss Mar 15 at 3:17

1 Answer 1

Express all in base $\;a\;$ (change of base property):

$$\log_ab\cdot\log_bc=\log_ab\frac{\log_ac}{\log_ab}=\ldots$$

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I feel embarrased ... I really don't believe that i did not see this . Thank you .ps don't have enough credit to vote up. –  FutureSci Mar 5 at 13:44

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