The natural logarithm of e is equal to 1. Using mathematical notation, the equation is written as ln(e) = 1, where e is a mathematical constant known as Euler's number and is equal to about 2.72.
The natural logarithm function is the log function to the base of e, rather than to the base 10, as with the function log(x). The natural log of e can be solved using the natural log's exponential properties, where the ln(e^x) is always equal to x when x is a number greater than zero. The reverse of this rule is expressed as e^ln(x) = x.