Therefore ln x y if and only if e y x. Alog a M M 3. But n log a x and m log a y from 1 and so putting these results together we have log a xy log a xlog a y So if we want to multiply two numbers together and find the logarithm of the result we can do this by adding together the logarithms of the two numbers.
Now the logarithmic form of the statement xy anm is log a xy n m.
Most calculators can directly compute logs base 10 and the natural log. In this lesson youll be presented with the common rules of logarithms also known as the log rules. Alog a M M 3. Log a a 1 4.