圆锥曲线中的一个重要的内容是求离心率的范围,它能很好地考察学生对圆锥曲线基本性质的运用能力,同时它往往与不等式综合在一起,对学生的思维能力要求较高.笔者在教学中发现学生在处理这类问题时障碍很大,思路混乱,条理不清,特别是不等式的构建往往无从下手.本文尝试通过一些典型例题,给出求离心率范围的常用策略,使学生 An important part of the conic is to find the range of eccentricity, which can be used to examine students ’abilities to use the basic properties of conics. At the same time, it is often integrated with inequalities and has a high demand on students’ thinking ability. In the process of teaching, it is found that students have a lot of obstacles in dealing with such problems, confusion and unclear ideas, especially in the construction of inequalities.In this paper, we try to find some common strategies to find out the range of eccentricity,