(1)sin(-5π/12) (2)cos(-61π/12)

来源：学生作业帮助网编辑：作业帮时间：2024/04/30 07:57:06

(1)sin(-5π/12) (2)cos(-61π/12)
(1)sin(-5π/12) (2)cos(-61π/12)

(1)sin(-5π/12) (2)cos(-61π/12)
(1)sin(-5π/12)=-sin(5π/12)=-cosπ/12=-√[(cosπ/6+1)/2]=-√[(√3+2)/4]=-(√6+√2)/4 (2)cos(-61π/12)=cos(-5π-π/12)=-cos(-π/12)=-cosπ/12=-(√6+√2)/4