The specific definition is as follows:
Positive integers: 1, 2, 3, 4, 5 ... (including 0)
Negative integers:-1, -2, -3, -4, -5. ...
Zero: 0
Positive scores: such as 1/2, 3/4, 5/6. ...
Negative scores: such as-1/2, -3/4, -5/6. ...
Finite decimal: a decimal that can be expressed by a finite number, such as 0.25, 2.75, etc.
Infinitely circulating decimal: one or more digits in the decimal part are infinitely repeated, such as1/3 = 0.3333 ..., 2/7 = 0.285714285714 ...
It should be noted that rational numbers are a special form of real numbers, which can be expressed by fractions or decimals. Rational number is a basic concept in mathematics, which involves basic operations such as addition, subtraction, multiplication and division, comparison of size and absolute value.
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Rational number is a basic concept in mathematics, which is defined as a real number that can be expressed as the ratio of two integers, including positive number, negative number and zero. In junior high school mathematics, learning rational numbers is a very important step, because it lays a solid foundation for subsequent mathematics learning.
The definition of rational number can be traced back to ancient Greece. At that time, people mainly used natural numbers to calculate, but with the development of society and the increase of actual demand, people began to think about how to deal with the quantity that is not completely divisible, so the concept of rational numbers came into being.
A rational number is obtained by dividing two integers, where the numerator is an integer and the denominator is an integer not equal to zero. For example, 2/3, -4/5, 0, 10 are all rational numbers. It should be noted that the denominator is not equal to zero, because division is meaningless when the denominator is zero.
Rational number can be expressed as a point on the number axis, with positive numbers on the right side of the number axis, negative numbers on the left side of the number axis and zero in the center. In this way, rational numbers can form an ordered sequence after being divided according to the number axis, which is convenient for comparison and calculation.
In junior high school mathematics teaching, students should not only master the definition and basic properties of rational numbers, but also master the addition, subtraction, multiplication and division of rational numbers and their mixed operations. In addition, students need to master the concepts of absolute value, reciprocal and reciprocal of rational numbers, and can apply these concepts to solve practical problems.
In a word, rational number is a very basic and important concept in mathematics, and students need to intuitively understand its meaning and nature with the help of number axis. Only by mastering the basic concept of rational numbers can we further learn other higher-level mathematical knowledge.