化简【cos(π/4+α)-sin(π/4+α)】/【cos(π/4-α)+sin(π/4-α)】.如题

问题描述:

化简【cos(π/4+α)-sin(π/4+α)】/【cos(π/4-α)+sin(π/4-α)】.如题

用二弦归一化简~很快的~