抛物线的几何定义与轨迹演示
2017-11-02 03:02
本范例直观演示了抛物线的几何定义及其轨迹生成过程。抛物线是平面上到一个定点（焦点）和一条定直线（准线）距离相等的点的集合。通过GeoGebra构造，设定焦点F和准线g，引入动点P。系统实时计算并显示动点P到焦点F的距离以及P到准线g的垂直距离。通过拖动点P，可以清晰地观察到这两段距离始终保持相等，从而生动地验证了抛物线的核心几何性质，帮助学习者深入理解圆锥曲线的定义。
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