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Slicktacker
Jun24-04, 02:41 PM
Does
(\log_{x}a - \log_{x}b - \log_{x}c) = \log_{x}(\frac{a}{b/c})?

chroot
Jun24-04, 02:48 PM
No, it equals

\log_{x}(\frac{a}{b \cdot c})

Perhaps you just made a mistake. a/b divided by c is a/(b \cdot c).

- Warren

chroot
Jun24-04, 03:03 PM
An easy way to remember this is to remind yourself of the log rule:

\log_x a^{-1} = - \log_x a

Whenever you see a minus sign in front of a log, mentally convert it to a plus sign and apply a -1 exponent to the argument. Then, when you add the logs, you multiply the arguments:

a \cdot b^{-1} \cdot c^{-1} = \frac{a}{b \cdot c}

- Warren

HallsofIvy
Jun26-04, 10:39 AM
\log_{x}(\frac{a}{b/c})
would be
(\log_{x}a - (\log_{x}b - \log_{x}c))

see the difference?