椭圆的定义：基于两圆的几何作图与轨迹构造
2018-05-01 00:28
本范例演示椭圆的经典几何定义与构造方法。通过两个辅助圆（分别对应椭圆长轴和短轴），利用正交线、交点与轨迹命令，动态生成椭圆上的点并描绘其完整轨迹。用户可拖动控制点观察椭圆形状的变化，直观理解椭圆参数与几何性质之间的关系。涉及的核心概念包括：圆的交点、正交投影、轨迹生成，是解析几何与几何作图的典型教学案例。
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