椭圆的轨迹：动圆与定圆相切的几何构造
2013-06-19 07:00
本范例通过几何作图直观演示椭圆的轨迹生成原理。通过构造一个动圆，使其与给定的大圆和小圆分别相切，利用动圆圆心到两定圆圆心距离之和为定值的几何性质，生动展示椭圆的定义与轨迹形成过程。该构造涉及圆、点、线段、角平分线及交点等基础几何对象，完美契合解析几何中圆锥曲线的教学与探索。
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