探究过圆内一点且与已知圆相切的动圆圆心轨迹
2015-11-12 01:00
本GeoGebra范例演示了几何轨迹的构造与性质。给定一个已知圆与圆内一定点，构造一个过该定点且与已知圆相切的动圆。透过几何作图（如线段中垂线、交点与轨迹命令），追踪动圆圆心的运动路径。范例直观地展示了该圆心轨迹实际上是一个椭圆，并结合了缩放与参数曲线等概念，帮助学习者深入理解椭圆的几何定义及其与圆的相切关系。
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