分类讨论是中学数学中一种重要的思想方法和解题策略.它是逻辑划分思想在解数学题中的具体应用,这种数学思想方法几乎涉及了中学数学的各个部分,如复数分为实数和虚数两类;实数又分为有理数和无理数两类.在高考中,由概念、公式引 Classification discussion is an important thinking method and problem solving strategy in middle school mathematics. It is a logical application of logical division of ideas in the solving of mathematics problems. This kind of mathematics and thinking methods involves almost every part of middle school mathematics, such as plurals into real numbers. There are two types of imaginary numbers; real numbers are divided into rational numbers and irrational numbers. In the college entrance examination, they are introduced by concepts and formulas.