Logarithm
 Allow large number ranges to be expressed over a smaller range of numbers, eg decibel scale. Also, multiplication and division may be expressed as simple addition and subtraction. Invented by Scottish mathematician John Napier in 1614.
 The power to which a base must be raised to yield a given number, usually abbreviated to;
 where b is the base. Common logarithms have base 10. Natural logarithms have base e, and are usually expressed;

 To change logarithm base;
 Logarithms are used to simplify multiplication, division and exponentiation.
 For example;
 Examples
 log_{10}(2) = 0.301029995664
 log_{10}(3) = 0.477121254720
 log_{10}(e) = 0.434294481903
 log_{10}(π) = 0.497149872694
 log_{e}(2) = ln(2) = 0.693147180560
 log_{e}(3) = ln(3) = 1.098612288668
 log_{e}(10) = ln(10) = 2.302585092994
See also: Exponent, Napier, John, Neper.
Subjects: Algebra