directrix

directrix的音标为[dɪ"rektɪs]，基本翻译为“中线，中轨，中迹”。速记技巧可以考虑使用谐音法，例如：“直列”可以帮助记忆directrix的含义和用法。

directrix的英文词源：

直接词源为拉丁语directrix，意为“导向者”。

变化形式：

1. 名词形式：directrix，directive。

2. 形容词形式：directive。

相关单词：

1. directive n.指令；指挥；指导原则；adj.指导的；指挥的。

2. direction n.方向；方位；指导；用法说明；v.指导；指挥。

3. director n.导演；指挥者；主管；理事。

4. directive direction 指令式方向。

5. directive principle 指导原则。

6. directional adj.方向的；指示的。

7. directional a.指向的；导向的；趋向的。

8. direct v.指挥；指导；使直接联系；使直接到达。

9. directive a.指挥的；指导的。

10. directive method 指令法。

以上单词都与directrix有着一定的关联，并具有不同的词义和用法。

常用短语：

1. directrix curve 直线的法线

2. directrix circle 直线的法线圆

3. directrix ellipse 直线的法线椭圆

4. directrix parabola 直线的法线抛物线

5. directrix hyperbola 直线的双曲线法线

6. on the directrix 在法线上

7. off the directrix 偏离法线

双语例句：

1. The parabola is defined by its focus and its directrix.

抛物线由其焦点和法线定义。

2. The graph of an ellipse lies between the major and minor axes and its directrix.

椭圆图位于长轴和短轴之间以及其法线上。

3. The point is off the directrix of the hyperbola.

该点偏离了双曲线的法线。

4. The graph of a circle is defined by its center and its directrix.

圆的图形由其中心和法线定义。

5. The line is parallel to the directrix and passes through the focus of the ellipse.

该直线平行于椭圆法线且通过椭圆的焦点。

6. The graph of a conic section is determined by its base and its directrix.

圆锥曲线图由其底和法线确定。

7. The parabola is a special case of a conic section, with its focus at the vertex and its directrix at infinity.

抛物线是圆锥曲线的一种特殊情况，其焦点在顶点上，其法线在无穷远处。

英文小作文：

The beauty of mathematics lies in its simplicity and elegance. One of the most fascinating topics in mathematics is curves, especially those related to geometry. Among these curves, the directrix curve is a crucial concept that plays a significant role in understanding various geometric figures.

The directrix curve represents the direction or path that a line or curve follows. It provides a framework to understand how different geometric figures are related to each other and how they behave under certain conditions.

For instance, when we talk about ellipses, we refer to a figure formed by two intersecting circles where one circle is fixed and the other circles revolves around it. The fixed circle’s center forms the center of the ellipse, while the direction in which the other circles revolves determines the directrix curve of the ellipse. Similarly, when we talk about hyperbolas, we refer to a figure formed by two intersecting parabolas where one parabola expands as it approaches infinity while the other shrinks to a point. The direction in which one parabola expands determines the directrix curve of the hyperbola.

The directrix curve is not only fascinating from a mathematical perspective but also has numerous applications in various fields such as engineering, physics, and astronomy, among others. Understanding this concept helps us gain a deeper understanding of geometric figures and their relationships, which in turn, enhances our ability to solve problems and create innovative solutions in various contexts.