圆锥曲线是历年高考数学的重点、难点内容,是学生最头疼、最难得分的一部分,很多学生在做圆锥曲线的题目时找不到相应的解题思路.笔者通过深入了解发现很多学生对定义理解不够透彻,不能灵活地利用定义是其失误的一部分原因.圆锥曲线的定义在求轨迹方程、最值及周长等问题中应用广泛.下面就圆锥曲线的定义在高考题中的应用举例说明.一、利用圆锥曲线定义求轨迹方程 Conic curve is the focus of college entrance examination math over the years, the difficult content is the most troublesome students, the most difficult part of the score, many students can not find the problem of coning the corresponding problem-solving ideas.The author through in-depth understanding of many students found that the definition Understanding is not thorough enough, can not flexibly use the definition is part of the reason for its error.The definition of the conic in the pursuit of trajectory equations, the most value and the circumference of the problem is widely used in the following conical curve definition of the application in the college entrance examination questions First, use the conic definition to find the trajectory equation