圆锥曲线 (椭圆、双曲线、抛物线 )的一个共同特性是 ,曲线上任意一点到焦点的距离和到相应准线的距离的比等于其离心率 .那么当给定了圆锥曲线的图形 (包括焦点的位置 )后 ,怎样画出该曲线的准线 ?这是教学中经常遇到的问题 .下面介绍一种利用直尺和圆规 (简称尺规 )画圆锥曲 A common characteristic of conical curves (ellipses, hyperbolas, parabolas) is that the ratio of the distance from any point on the curve to the focal point and the distance to the corresponding guideline is equal to its eccentricity. Then when given the conic curve’s shape (including the focus How to draw the guideline of the curve after the position of the position. This is a problem often encountered in teaching. Here is a description of a conical song using a ruler and a compass (referred to as a ruler).