Real numbers include rational numbers and irrational numbers. Among them, irrational number is infinite acyclic decimal, and rational number includes integer and fraction. Mathematically, real numbers are intuitively defined as numbers corresponding to points on the number axis.

Real numbers have a wide range of applications, so it can be said that real numbers do not start in life.

The basic operations that real numbers can realize are addition, subtraction, multiplication, division, multiplication and so on. For non-negative numbers (that is, positive numbers and 0), you can also perform a root operation. The result of addition, subtraction, multiplication, division (divisor is not zero) and square of real numbers is still real numbers. Any real number can be raised to an odd power, and the result is still a real number. Only non-negative real numbers can be raised to even powers, and the result is still real numbers.