Therefore log 5 25 2. For other natural logarithms we can use the ln l n key that can be found on most scientific calculators. The number b b is called the base.
One the base and the number in the parenthesis are identical the exponent of the number is the solution to the logarithm.
Remembering this equivalence is the key to evaluating logarithms. Logarithm rules Logarithm product rule. To solve this type of equations here are the steps. Y logbx is equivalent to x by y log b x is equivalent to x b y The first is called logarithmic form and the second is called the exponential form.