In 1 equals 0. No matter what the base of logarithm is, when N= 1, the value is equal to 0. If the x power of a is equal to n (a >; 0, and a is not equal to 1), then the number x is called the logarithm of n with a as the base, and is recorded as x=logaN.

function

Function was originally translated by Li, a mathematician of Qing Dynasty in China, in his book Algebra. He translated this way because "whoever believes in this variable is the function of that variable", that is, the function means that one quantity changes with another quantity, or that one quantity contains another quantity.