深刻领会圆锥曲线的定义是进一步学习圆锥曲线的标准方程,几何性质和应用的基础,但在教学中发现,刚开始学习时,学生虽然会背圆锥曲线的定义,但在碰到具体问题时由于不会用定义进行分析,而导致没有思路或即使找到解题思路,也往往由于计算繁杂,算理不明,计算能力不过硬等问题做不出最终结果而导致半途而废,事倍功半。本文将通过对三组题目的分析,帮助同学们领会如何活用圆锥曲线的定义来优化解题过程,以期起到抛砖引玉的目的。 Deep understanding of the definition of the conic is to further study the standard equation of conic, geometric properties and application of foundation, but found in teaching, just started learning, although students will back conic definition, but in the face of specific problems due to Will not use the definition of analysis, which led to no ideas or even find solutions to problems, but also often due to complicated calculations, arithmetic is not clear, the computing power is not enough, and other issues can not make the final results and lead to halfway, with less effort. This article will analyze the three groups of topics to help students understand how to use the definition of conic to optimize the problem-solving process, in order to play a role in attracting valuable comments.