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为什么准线和焦点轴垂直
更新时间: 2021-01-16 13:28:09  

1、因为准线的定义就是垂直于长轴所在直线的直线。也就是垂直于焦点轴。

2、在圆锥曲线的统一定义中:到定点与定直线的距离的比为常数e(e>0)的点的轨迹,叫圆锥曲线。而这条定直线就叫做准线(Directrix)。0

关键词: 为什么 准线 焦点 垂直

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