《全日制普通高中数学课程标准(实验稿)》明确指出,“教学中应通过实例引导学生运用合情推理去探索、猜测一些数学结论,并用演绎推理确认所得结论的正确性,或者用反例推翻错误的猜想”.所谓反例,简单来说,就是用来证明某个判断或说法不正确、不成立的例子.教师恰当的运用反例,一方面会把数学中某些概念的本质特征以及定理的相关条件突出地衬托出来,使学生对比相关概念、定理结论反思自己的误解,加深对概念本质 “Full-time ordinary high school mathematics curriculum standards (experimental draft)” clearly states that “teaching should guide students to use case-based reasoning to explore, guess some mathematical conclusions, and use deductive reasoning to confirm the conclusions of the correctness, or use counter examples Overthrow the wrong guess. ”The so-called counterexample, in simple terms, is used to prove that a judgment or argument is not correct, not an example of the proper use of counterexamples teachers, on the one hand will be the essence of some concepts in mathematics and theorem The relevant conditions prominently set off to enable students to compare concepts, conclusions of the theorem reflection on their own misunderstanding, deepen the concept of essence