来自罗建军的问题
【sin(π/12)=怎么算】
sin(π/12)=
怎么算
1回答
2020-06-09 22:55
【sin(π/12)=怎么算】
sin(π/12)=
怎么算
sin(π/12)
=sin(4π/12-3π/12)
=sin(π/3-π/4)
=sinπ/3cosπ/4-sinπ/4cosπ/3
=√3/2×√2/2-√2/2×1/2
=√6/4-√2/4
=(√6-√2)/4
参考公式:
sin(a-b)=sinacosb-sinbcosa