Such functions are used in solving exponential equations .
Logarithmic functions turn multiplication into addition.
Before the advent of calculators, first tables of logarithms and then slide rules based on logarithms were used as an aid to multiplication. The natural logarithm is the one which has the nicest purely mathematical properties and is the one which we use almost exclusively in calculus. The common logarithm of x, often written simply as log x, is the logarithm to the base 10. If x is an integer, this measures the number of bits it takes to write x. We will not use this notation in CalculusQuest TM .