Also known as focus of a parabola, directrix circle, focuses, foci
fixed reference point; special points with reference to which any of a variety of curves is constructed
In the Vinony graph
Within Vinony's link graph, 焦點 is referenced by 118 other articles, and connects out to semi-axis, Earth and Sun.
It is catalogued under topics including Conic sections and Geometric centers.
Its subject is documented across 30 Wikipedia language editions.
Article · 中文
在几何学上，焦點是指建構曲線中的一些特殊點。例如用一個或二個焦點可以定義圓錐曲線，分別為圓（一個焦點）、橢圓（二個焦點）、拋物線（一個焦點和一條線）及雙曲線（二個焦點），此外，有二個焦點可以定義卡西尼卵形线及，二個以上的焦點可以定義。
Abstract from DBpedia / Wikipedia · CC BY-SA