塞瓦定理是平面几何中证明线共点问题的一个重要定理,利用它证明现行中学几何教材中有关三角形的几个三线共点问题时,不仅使此类问题的证法得到统一,而且证题思路简捷明快,对拓宽学生的知识面,提高证题技巧,培养能力都有一定的帮助,本文就此举例如下,以供参考。 The Seva theorem is an important theorem of the problem of the coincident point of the proof line in plane geometry. It is used to prove that the three lines of common triangles in the current middle school geometry textbook not only make the proof of this type of problem uniform, but also prove that The idea is simple and clear, and it will help to broaden the students’ knowledge, improve the skills of the questions, and cultivate their abilities. This article gives examples for the following, for reference.