Mathematically, ln represents the natural logarithm, and the logarithm of the natural logarithm based on the constant e is called lnn(n >；; 0)。 It is of great significance in physics, biology and other natural sciences. The general representation is lnx. Logx is also commonly used in mathematics to represent natural logarithm. In order to avoid confusion with the commonly used logarithm lgx based on 10, you can use "write all" ex. Among them, the concept of logarithm began with 16 14. Six years later, John Napier and Jost burgui published their own logarithmic tables.