若θ属于[π/4,π/2],sin2θ=3根号7/8,则sinθ=?
若sin(π/4+α)=sinθ+cosθ,2sin^2β=sin2θ,求证:sin2θ+2cos2β=3
已知cosθ =-(根号2)/3,θ 属于(π/2,π),求2/sin2θ -cosθ/sinθ
已知sinα-cosα=根号2,α属于(0,π),则sin2α=
若θ属于(pi/4,pi/2),sin2θ=1/16,则cosθ-sinθ=?
若sin2α=sinα+cosα,则根号2*sin(α+π/4)等于多少
Θ∈(π/2,3π/4) sin2Θ∈a sinΘ+cosΘ
设sin(π/4+θ)=1/3,则sin2θ=
若2sin(π4+α)=sin θ+cos θ,2sin2β=sin 2θ,求证:sin&
若2sin(π/4+θ)=sinθ+cosθ,2sin^2(β)=sin2θ,求证sin2α+1/2cos2β=0
若2sin(π/4+a)=sinθ+cosθ,2sin^2β=sin2θ,求证sin2a+(1/2)cos2β=0.
若2sin(π/4+a)=sinθ+cosθ,2sin^2β=sin2θ,求证sin2a+(1/2)cos2β=0
已知sin(θ+π/4)=1/3,求sin2θ