椭圆：利用顶点与焦点控制椭圆大小
2013-06-10 01:46
本GeoGebra范例演示椭圆的几何构造。通过拖动两个顶点A、B可动态控制椭圆的大小与形状。构造中包含椭圆的两个焦点F₁、F₂，以及长轴(FirstAxis)和短轴(SecondAxis)。该范例直观展示了椭圆的基本要素——顶点、焦点、长短轴之间的几何关系，帮助学习者理解椭圆作为圆锥曲线的核心性质，包括焦点到椭圆上任意一点距离之和为常数这一定义。适用于解析几何与圆锥曲线教学。
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