(1)已知sinθ+2cosθ=0,计算:2sin^θ-3sinθcosθ+5cos^θ=?
已知(4sinθ-2cosθ)/(3sinθ+5cosθ)=6/11,求5cos^2θ/(sin^2θ+2sinθcos
已知θ为第三象限角,1-sinθcosθ-3cos^2=0则5sin^2θ+3sinθcosθ=?
已知 sin(θ+kπ)=-2cos (θ+kπ) 求 ⑴4sinθ-2cosθ/5cosθ+3sinθ; ⑵(1/4)
求证sinθ/(1+cosθ)+(1+cosθ)/sinθ=2/sinθ
已知2sinθ+3cosθ=2,求sinθ+cosθ的值
已知y=2sinθcosθ+sinθ-cosθ(0
已知sinθ+2cosθsinθ−cosθ=3,求值:
已知tanθ=根号2,求(1)(cosθ+sinθ)/(cosθ-sinθ);(2)sin²θ-sinθcos
化简:1+sinθ+cosθ+2sinθcosθ /1+sinθ+cosθ
求证:(1+cosθ+cosθ/2) /(sinθ+sinθ/2)=sinθ/1-cosθ
已知向量a=(sinθ,cosθ-2sinθ),向量b=(1,2) 求tanθ 求sinθ*cosθ-3cos^2θ
sin^2θ/sinθ-cosθ + cosθ/1-tanθ = sin^2θ/sinθ-cosθ + cosθ/1-(