求cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11)求值:cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11)(5/24)(11/24)=5/11?,而且过程和题好像都没关系。

求值:cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11) 求值：cos(π/11)-cos(2π/11)+cos(3π/11)-cos(4π/11)+cos(5π/11) cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11) 求cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11)求值:cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11)(5/24)(11/24)=5/11?,而且过程和题好像都没关系。 利用诱导公式求三角函数值 cos 6/65π一,利用诱导公式:cos（2kπ+α）=cosα （k∈Z）和cos（π－α）=－cosα 得出cos65π/6=cos(65π/6-10π)=cos(5π/6)=cos(π-π/6)=-cosπ/6=-√3/2二,又或者cos65π/6=cos(11π-1π/6)=-cos( cos（π/11）cos（2π/11）cos（3π/11）cos（4π/11）cos（5π/11）怎么解 三角函数计算cosα=1／7,cos（α+β）=-11／14,α、β∈（0,π／2）,求cosβ 已知COSα=1/7,COS（α+β）=-11/14,且α,β属于0到2/π,求COSβ 已知cosα=1/7,cos（α+β）=-11/14,且α、β∈（0,2/Π）,求cosβ的值 求cos(2π/7)*cos(4π/7)*cos(6π/7)的值 怎么求cosβ的值已知cosα=1/7,cos(α+β)=-11/14,且α∈(0,π/2),α+β∈(π/2,π),求cosβ的值 求cos(π/2+α)sin(-π-α) / cos(11π/2 -α)sin(9π/2+α)的值 求SINπ/64 COSπ/64 COSπ/32 COSπ/16 COSπ/8 cos(-A-11π/2) =cos(A+11π/2)怎样计算来的? 计算：cos（π/5)+cos（2π/5)+cos(3π/5)+cos(4π/5) cos(π/17)*cos(2π/17)*cos(4π/17)*cos(8π/17) cos^2α+cos^2(α+π/3)-cosαcos(α+π/3)化简 已知cos(5π/12-α)=m(lml≤1),求cos(π/12+α)和cos(11π/12-α)的值