论文部分内容阅读
求轨迹方程是解析几何的两个基本问题之一,它能全面考查同学们的数学能力与数学思想及逻辑思维能力、分析解决问题的能力。它因形式灵活多样、解法精妙而在解析几何中占有重要的地位,成为历年高考命题的热点。下面以2013年全国各地高考题为例对求轨迹方程的常用方法加以归纳总结,以帮助同学们系统的复习。一、直接法把几何等量关系“翻译”成含“x,y”的代数式子并化简就能得到轨迹方程,这种方法称为直接法。例1(2013年陕西卷)已知动圆过定点A(4,0),且在y轴上截得的弦MN的长为8。
Seeking trajectory equation is one of the two basic problems of analytic geometry, it can fully examine the students’ mathematical ability and mathematical thinking and logical thinking ability, analyze the ability to solve the problem. It is flexible and diverse because of the form, the solution is exquisite and occupies an important position in analytic geometry, has become the hot topic of college entrance examination over the years. The following 2013 college entrance examination questions around the country as an example to find ways to track equations common to summarize to help students review the system. First, the direct method to geometric equivalent relationship “translation ” into “x, y ” algebraic equations and simplify the trajectory equation can be obtained, this method is called the direct method. Example 1 (Shaanxi Volume 2013) is known to have a fixed point A (4,0) and the length of the string MN taken on the y-axis is eight.