三角形的三线：高、中线与角平分线的几何作图
2019-08-01 15:08
本 GeoGebra 范例演示三角形中三种重要线段（高、中线、角平分线）的构造方法。通过 OrthogonalLine 命令作顶点到对边的垂线（高），Midpoint 与 Segment 命令连接顶点与对边中点（中线），AngularBisector 命令作内角平分线。范例涵盖三角形基本特殊线段与特殊点的几何性质，适合初中平面几何教学，帮助学生直观理解三角形三线的定义、作图步骤及其交点（垂心、重心、内心）的几何意义。
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