双曲线第一定义：焦点距离差的轨迹演示
2019-07-31 02:59
本GeoGebra范例演示双曲线的第一定义，即平面上到两个定点（焦点F₁和F₂）的距离之差的绝对值等于常数的点的轨迹。通过构造圆、线段、垂直平分线及交点等几何对象，动态展示双曲线上任意点P到两焦点的距离关系。拖动点P可观察距离差恒定的性质，直观理解双曲线的几何本质与焦点定义，适用于圆锥曲线教学与解析几何学习。
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动点P到两焦点F_1和F_2的\\距离
差为定值,
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