已知sin(30+α)=1/3,则cos(60-α)=?
来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/26 19:25:41
已知sin(30+α)=1/3,则cos(60-α)=?已知sin(30+α)=1/3,则cos(60-α)=?已知sin(30+α)=1/3,则cos(60-α)=?30+α+60-α=90cos(
已知sin(30+α)=1/3,则cos(60-α)=?
已知sin(30+α)=1/3,则cos(60-α)=?
已知sin(30+α)=1/3,则cos(60-α)=?
30+α+60-α=90
cos(60-α)=cos[90-(30+α)]=sin(30+α)=1/3
cos(60-α)
=cos[90-(30+a)]
=sin(30+a)=1/3
1/3
cos(60-α)=cos(90-30-α)=cos[90-(30+α)]=sin(30+α)=1/3
牛人多