For example two numbers can be multiplied just by using a logarithm table and adding. Log_ba-log_bc log_b beginpmatrix fracacendpmatrix Example The expression. X would have to be 4.
The logarithm of a number is the exponent by which another fixed value the base has to be raised to produce that number.
In fact logarithm with base 10 10 is known as the common logarithm. 2 Division inside the log can be turned into subtraction outside the log and vice versa. Observe the number above 4 of the D scale on the C scale. It is how many times we need to use 10 in a multiplication to get our desired number.