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关于求异面直线距离的问题,本刊以往各期已有几次介绍过。本文只介绍求异石直线的极值法,供参考。从二异面直线之一上的任一点作另一直线的距离把这些距离表示成某变量的函数,那末这个函数的极小值就是两条异面直线之间的距离。例1。正三角形SAB是等边圆锥的轴截面,BC是底面圆中的弦,且∠ABC=60°求SA与BC之间的距离解:设底面圆的半径为1,在SA上任取一点M,作MN上
With regard to the problem of seeking straight-line distances from different sides, we have already introduced several times in previous issues. This article only introduces the extremum method for the straight line of different stones, for reference. The distance from any point on one of the two different straight lines to another straight line represents these distances as a function of a variable, and then the minimum value of this function is the distance between two different straight lines. example 1. The regular triangle SAB is the axial section of an equilateral cone, BC is the chord in the bottom circle, and ∠ABC=60° Find the distance solution between SA and BC: Let the radius of the bottom circle be 1 and take any point M on the SA. For MN