已知cos(θ+π/6)=-5/13,θ∈(π/2,π),则sin(θ+π/6)的值
已知cos(θ+π/6)=-5/13,θ∈(π/2,π),则sin(θ+π/6)的值
已知tanθ=3,求(3cosθ-5sin^2θcosθ)/sin(π-θ)的值
已知6sin^2θ+sinθcosθ-2cos^2θ=0,θ∈[π/2,π]求cos2θ的值
已知θ∈(-π/2,0),cosθ=13,求sinθ+cos(θ-π/4)的值
已知sinθ+cosθ=1/5,且π/2≤θ≤3π/4,则cos^2-θsin^2θ的值
已知sin(θ+kπ)=2cos[θ+(k+1)π],k∈Ζ,求4sinθ-2cosθ/5cosθ+3sinθ的值
θ∈(0,π/2),比较cosθ、sin(cosθ)、cos(sinθ)的大小
已知tan(π/4 +θ)=2 则 1/(2sinθcosθ+cos^2 θ)的值为
已知 sin(θ+kπ)=-2cos (θ+kπ) 求 ⑴4sinθ-2cosθ/5cosθ+3sinθ; ⑵(1/4)
急求已知根号3sinθ-sin(π/2-2θ)/cos(π+θ)×cosθ=1 θ ∈(0,π) 求θ的值
已知锐角θ满足sin(πcosθ)=cos(πsinθ) 求sin2θ的值?
①化简[sin(2π+α)*cos(7π-α)]/cos(-α)②已知cosθ=-3/5,θ∈(π/2,π),求sin(