认识不同的角（一）
2014-11-10 14:38
本范例通过几何作图演示角的概念与构造。利用旋转命令和半圆等工具，动态展示点、线段与角之间的关系。通过观察旋转过程中的角度变化，帮助学习者直观理解角的定义、度量方法以及不同角度的几何特征，是学习基础几何与角度知识的优秀互动素材。
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