直线的参数方程及参数t的几何意义是简洁明快解决解析几何有关距离问题、中点问题、对称问题、范围问题等的重要工具.1预备知识:直线的参数方程及参数t的几何意义关于直线的参数方程,现行高中数学新教材都安排在选修4-4中,这些新教材对于参数t的几何意义一般都写得比较简略,多数学生感到难学、难懂、难用.基于此,本文给出一种不同于教材的推导 The straight line parameter equation and the geometric meaning of the parameter t are concise and crisp and important tools to solve the problem of analytic geometry about distance, midpoint, symmetry and range problems.1 Prerequisites: The parametric equation of the straight line and the geometric meaning of the parameter t About the straight line The current high school mathematics new textbooks are arranged in the elective 4-4, the new textbook for the geometric meaning of the parameter t are generally written relatively simple, most students feel difficult to learn, difficult to understand, difficult to use.Therefore, this article Give a different from the deduction of teaching materials