圆函数与双曲函数：旋转中的差异
圆函数与双曲函数之间的差异可通过旋转来理解。例如，cosh(z) = cos(iz) 表明，求 z 的双曲余弦相当于先将 z 左旋四分之一圈（即乘以 i），再求余弦。这一视角揭示了两种函数在复数域中的深层联系。
相关报道
The article discusses the relationship between circular and hyperbolic functions, showing that they differ by a rotation in the complex plane. Specifically, it demonstrates how cosh and sinh relate to cos and sin through multiplication by the imaginary unit i.