椭圆轨迹：内切于两定圆的动圆圆心轨迹
2013-06-11 03:20
本GeoGebra范例演示了经典的椭圆定义与轨迹问题。通过构造一个同时内切于给定大圆和小圆的动圆，追踪该动圆圆心的运动轨迹，直观地验证了动圆圆心到两定圆圆心的距离之和为常数，从而形成椭圆。范例包含输入框以动态调整大圆和小圆的半径，帮助学习者深入理解椭圆的几何性质、焦点与轨迹方程之间的关系，是解析几何与几何作图的优秀教学素材。
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