双曲线的几何定义：到两焦点的距离差
2014-06-23 08:28
本范例演示了双曲线的几何定义，即平面上到两个定点（焦点）的距离之差的绝对值为常数的点的轨迹。通过GeoGebra的几何作图命令（如点、圆、线段、中垂线及交点），动态展示了动点如何满足这一距离差条件并生成双曲线图形，帮助直观理解圆锥曲线的核心性质。
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