圆周长与弧长动态演示
2020-06-06 08:11
本 GeoGebra 范例通过线段(Segment)、旋转(Rotate)、圆弧(CircleArc)与圆(Circle)等构造命令，动态演示圆的周长及弧长与半径 r、圆心角 θ 之间的关系。用户可拖动滑块调节半径和角度参数，实时观察圆弧长度变化，直观理解圆周长公式 C=2πr 及弧长公式 l=rθ 的几何意义。适用于初中至高中阶段的几何教学，帮助学生建立圆周与角度的量化直觉。
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