已知角θ终边上一点P的坐标为(COS π/5,SIN π/5),则θ=?
问题描述:
已知角θ终边上一点P的坐标为(COS π/5,SIN π/5),则θ=?
RT..
答
=π/5 x为COS π/5 y为 SIN π/5所以tanθ=y/x=(SIN π/5)/(COS π/5)=tan π/5
所以θ=π/5