同学们都知道,不等式的基本性质有下列三条:①不等式的两边都加上(或减去)一个整式,不等号的方向不变;②不等式的两边都乘以一个正数,不等号的方向不变;③不等式的两边都乘以一个负数,不等号的方向改变.现通过举例,说说不等式基本性质的作用,供同学们学习时参考. Students all know that the basic properties of inequality have the following three items: ① inequality add (or subtract) an integral on both sides, the inequality of the same direction; ② both sides of the inequality are multiplied by a positive number, the inequality of the same direction ③ The inequality is multiplied by a negative number on both sides, and the direction of the inequality sign is changed. Now, by way of example, we will talk about the role of the basic nature of inequalities for reference when students study.