欧拉线：三角形外心、重心与垂心共线定理演示
2013-08-27 08:36
本范例演示三角形欧拉线定理，即任意三角形的外心、重心与垂心三点共线。通过构造三角形及其外接圆圆心（外心O）、三条中线交点（重心G）和三条高线交点（垂心H），利用平行四边形性质与重心将中线分为1:2的比例关系，直观展示三点共线的几何性质。范例涵盖多边形、圆、中点、垂线、向量等几何作图元素，帮助学习者深入理解三角形重要几何中心之间的内在联系与欧拉线的经典证明思路。
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