Positive integers and fractions are collectively referred to as positive rational numbers, and negative integers and fractions are collectively referred to as negative rational numbers. Therefore, the number of rational number sets can be divided into positive rational numbers, negative rational numbers and zero.
2. Properties of rational numbers: Mathematically, rational numbers are the ratio of integer A to integer B, for example, 3/8, and the general rule is that A/B..0 is also rational numbers. A rational number is a set of integers and fractions, and integers can also be regarded as fractions with a denominator of 1. The fractional part of a rational number is a finite or infinite cyclic number. Real numbers that are not rational numbers are called irrational numbers, that is, the fractional part of irrational numbers is infinite cyclic numbers.
3. Rational numbers include integers and fractions. The visual performance is as follows:
Extended data:
Law of rational number operation:
1, addition algorithm:
(1) additive commutative law: When two numbers are added, the position of the addend is exchanged and the sum remains unchanged, that is, (a+b)+c=a+(b+c).
(2) Law of addition and association: When three numbers are added, the first two numbers are added or the last two numbers are added first, and the sum is unchanged, that is, A+B = B+A.
2, subtraction algorithm:
Law of subtraction: subtracting a number is equal to adding the reciprocal of this number. Namely: a-b=a+(-b).
3, multiplication algorithm:
(1) Multiplication Commutativity Law: When two numbers are multiplied, the position of the exchange factor and the product remains unchanged, that is, ab=ba.
(2) Multiplication and association law: When three numbers are multiplied, the first two numbers are multiplied first, or the last two numbers are multiplied first, and the product remains unchanged, that is, (ab)c=a(bc).
(3) Multiplication and distribution law: a number is multiplied by the sum of two numbers, which means that this number is multiplied by these two numbers respectively, and then the products are added, that is, a(a+b)=ab+ac.
References:
Baidu Encyclopedia _ Rational Numbers