椭圆的定义（第一定义）几何作图演示
2020-03-10 00:37
本 GeoGebra 范例动态演示了椭圆的第一定义，即平面内到两个定点（焦点 F_1 和 F_2）的距离之和等于常数的点的轨迹。通过构造圆、线段的中垂线以及交点，利用轨迹命令（Locus）生成椭圆。用户可以直观地观察动点 P 运动时，线段 PF_1 和 PF_2 的长度变化及其和保持恒定的几何性质，是学习解析几何和圆锥曲线的经典教学工具。
所属专题
中职数学GeoGebra互动教学资源库
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