尺规作图：作一个角等于已知角
2020-12-24 08:23
本 GeoGebra 范例演示了经典的尺规作图问题：如何仅使用无刻度直尺和圆规，作一个角使其等于已知角。构造过程涉及画圆、求交点、作线段及圆弧等基本几何操作，展示了欧几里得几何中全等三角形的判定原理（SSS）在作图中的应用。适合初中几何教学与尺规作图基础学习。
所属专题
点、线、角：基础几何互动教程
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拖动点A改变\angle AOB的大小\\当\angle AOB=180\degree时，只执行第1步、第5步即可""/>
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