化简[sin(α+π/ 6)-sin( α-π÷6)]÷cosa
化简sin平方(a-6/π)+sin平方(a+6/π)-sin平方a
高二数学tanα=根号3/3,则cosa^2-sin(α+π/6)cosα的值是多少
已知sin(a+π/6)+cosa=4/5倍根号3,则sin(a+π/3)=
1.化简sin²α+cosαcos(π/3+α)-sin²(π/6-α)
化简:sin2a/sin(π+a)+cos2a+1/cosa
化简:sin(a-B)cosa-1/2[sin(2a+B)-sinB]=?已知cos(a-π/6)+sina=4√3/5
已知向量a=sin((a+π/6),1),b=(4,4cosa-根号3) a垂直b 则sin(a+4π/3)的值
化简sina^8-cosa^8-sin^6a+cos^6a+sin^4a
1.已知cosa=3/5 a属于(0,π/2)求sin(a-π/6)的值
已知sin(a+π/6)=4/5 a∈(0,π/3) 求cosa
已知sin(π÷6-α)=1÷4,则sin(π÷6+2α)=
化简:1、sin(x-π/3)-cos(x+π/6)+√3cosx=?2、已知,sinα+sinβ=√2/2,求cosα