诱导公式二：y轴对称的三角函数关系
2020-03-13 13:06
本范例演示三角函数诱导公式二中关于y轴对称的几何关系。通过在坐标系中构造角θ及其关于y轴的对称角π-θ，直观展示正弦、余弦和正切值在y轴反射下的变化规律。利用镜像变换（Mirror）和动态参数，用户可观察对称点P'的坐标变化，理解sin(π-θ)=sinθ、cos(π-θ)=-cosθ、tan(π-θ)=-tanθ等公式的几何本质，帮助建立三角函数诱导公式的直观认知。
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中职数学GeoGebra互动教学资源库
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