利用定义求sin7π/3,cos7π/3,tan7π/3.
问题描述:
利用定义求sin7π/3,cos7π/3,tan7π/3.
答
sin7π/3=sin(7π/3-2π)=sinπ/3=2分之根号3
cos7π/3=cos(7π/3-2π)=cosπ/3=2分之1
tan7π/3=tan(7π/3-2π)=tanπ/3=根号3.