数与式【考纲扫描】本章包括有理数、实数、代数式、整式与分式等内容.本章涉及到的内容大都是基础知识和基本技能.主要知识点及要求如下:1.会用负数表示有关量;会用有理数估计一个无理数的大致范围;会对含有较大数字的信息作出合理的解释和推断.2.会根据相反数、倒数、绝对值? Numbers and Formulas [Summary Scan] This chapter includes rational numbers, real numbers, algebraic expressions, integers and fractions, etc. The contents covered in this chapter are mostly basic knowledge and basic skills. The main knowledge points and requirements are as follows: 1. Negative numbers will be used to indicate the relevant quantities. The rational number will be used to estimate the approximate range of an irrational number; reasonable explanations and inferences will be made on information with larger numbers. 2. Will be based on the inverse number, reciprocal, absolute value?