二倍角正切公式的几何证明
2020-04-10 02:08
本GeoGebra范例通过几何作图方法证明二倍角的正切公式 tan(2α) = 2tan(α)/(1-tan²(α))。利用射线、圆、角、垂线、镜像等几何构造元素，构建包含多个角度（α、β、γ、δ等）的几何图形，直观展示二倍角正切公式的几何意义与推导过程。该范例将三角恒等式转化为可视化的几何关系，帮助学生深入理解正切二倍角公式的本质，适用于高中三角函数教学与自主探究学习。
所属专题
中职数学GeoGebra互动教学资源库
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