画法几何精确图解个教规律研究

SEVERAL RULES ON PRECISE DIAGRAM OF DESCRIPTIVE GEOMETRY

以画法几何常见作图题为例.分析用直尺和圆规作图时可能出现交点.个数的方法得知:其多解个数是遵循2n(n=0,n=N.n<4)个解的规律,从而使求解具体生产问题时不致漏掉最佳解.并用解析几何法,在解题之进就判断出不可解的题。

This article tries to seek SEVERAL RULES ON PRECISEDIAGRAM OF DESCRIPTIVE GEOMETRY.Though the way of analy-zing the number of point intersection which may apper in drawing andthe way of Analytical Geometry author obtains that the number of com-plex soluttion is in accordance to the law oe the solution:2~n(n=0,n∈N)n<4),Before solving problems,using this way can jndge which is unsol-vable.So it can save time and energy.