| 单词 | focal line |
| 释义 | > as lemmasfocal line focal line n. Geometry (a) a line which intersects with or terminates in the focus of a geometric figure; †(b) the focal conic of the cone which consists of two intersecting lines, regarded as a degenerate hyperbola (obsolete rare). ΚΠ 1794 G. Walker Treat. Conic Sections i. 101 The rectangular under the segments of each between the focus and section or sections, shall be to each other as the segments of the focal lines, intercepted between the section or sections. 1862 G. Salmon Treat. Analytic Geom. Three Dimensions vii. 104 The focal lines of the cone..are plainly the asymptotes to the focal hyperbola of the surface. 1871 Dublin Exam. Papers for 1870 23 The angle between one tangent and one focal line is equal to the angle between the other tangent and the other focal line. 2009 D. Kalman Uncommon Math. Excursions vi. 121 With calculus and analytic geometry, we can find the equations of the ellipse, tangent, and focal lines. < as lemmas |
| 随便看 |
英语词典包含1132095条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。