What do you mean by positive, negative, positive and negative? Positive is positive, negative is positive and negative is negative, which refers to the multiplication law of rational numbers. Rational number multiplication rule: two numbers are multiplied, the same sign is positive and the different sign is negative. Any number multiplied by 0 is 0. When several numbers are not equal to 0, the sign of the product is determined by the number of negative factors. When there are odd negative factors, the product is negative, and when there are even negative factors, the product is positive.

Rational number is the collective name of integer (positive integer, 0, negative integer) and fraction, and it is the set of integer and fraction. Integers can also be regarded as fractions with a denominator of one. Real numbers that are not rational numbers are called irrational numbers, that is, the fractional part of irrational numbers is infinite cyclic numbers. It is one of the important contents in the field of number and algebra, and it is widely used in real life. It is the basis for continuing to learn real numbers, algebraic expressions, equations, inequalities, rectangular coordinate systems, functions, statistics and other mathematical contents and related disciplines. The set of rational numbers can be represented by the capital black orthographic symbol Q, but Q does not represent rational numbers. The set of rational numbers and rational numbers are two different concepts. The set of rational numbers is the set of all rational numbers, and rational numbers are all elements in the set of rational numbers.