三角函数计算
cos 30sin 40cos 50+ cos 40sin 50sin60 要过程 谢谢
cos 30sin 40cos 50+ cos 40sin 50sin60 =[(√3)/2]sin 40cos 50+[(√3)/2]cos 40sin 50 =[(√3)/2](sin 40cos 50+cos 40sin 50) =[(√3)/2](sin 40cos 50+cos 40sin 50) =[(√3)/2]sin (40+50) =(√3)/2
原式=sin60sin 40cos 50+ cos 40sin 50sin60 =sin60(sin 40cos 50+ cos 40sin 50 ) =sin60sin(40+50) =√3/2*sin90 =√3/2*1 =√3/2
答:cos(arctan√3+π/3) =cos(π/3+π/3) =cos2π/3 =-cosπ/3 =-√3/2详情>>
答:详情>>