In the real number field, if the real number formula has no root number, then as long as the real number formula is greater than zero, if there is a root number, it is required that the real number is greater than zero, the formula in the root number is greater than or equal to zero (if it is negative, the value is imaginary), and the radix is greater than 0, not 1.

Why is the base of logarithmic function greater than 0 instead of 1? In the ordinary logarithmic formula, a

Usually, we call the logarithm with 10 as the common logarithm, and record log 10N as lgN. In addition, the logarithm based on irrational number E = 2.7 1828 is often used in scientific counting. The logarithm based on E is called natural logarithm, and logeN is recorded as InN.

From the end of 16 to the beginning of 17, at that time, the development of natural sciences (especially astronomy) often encountered a large number of accurate and huge numerical calculations, so mathematicians invented logarithms in order to seek simplified calculation methods.

Two series of integer arithmetic written by Steve (1487- 1567) in Germany with 1544. On the left, the geometric series is called the original number, and on the right, the representative of the arithmetic series is called the original number, or exponent. German is Exponent, which means representative.

If you want to find the product (quotient) of any two numbers on the left, you only need to find the sum (difference) of its representative (exponent) first, and then put this sum (difference) on a primitive number on the left, then this primitive number is the product (quotient) you want. Unfortunately, Steve did not explore further and did not introduce the concept of logarithm.

Napier is quite good at numerical calculation. The "Napier algorithm" he created simplifies the multiplication and division operation, and its principle is to replace multiplication and division with addition and subtraction. His motivation for inventing logarithm is to find a simple method to calculate spherics. He constructed the so-called logarithmic method based on a very unique idea related to particle motion.

Its core idea is the connection between arithmetic progression and geometric sequence. He expounded the principle of logarithm in Description of Wonderful Logarithm Table published by 16 19, which was later called Napier Logarithm and recorded as Nappe. X,