COSθ-SINθ=√2COS(θ+π/4) 0
θ∈(0,π/2),比较cosθ、sin(cosθ)、cos(sinθ)的大小
已知(4sinθ-2cosθ)/(3sinθ+5cosθ)=6/11,求5cos^2θ/(sin^2θ+2sinθcos
已知 sin(θ+kπ)=-2cos (θ+kπ) 求 ⑴4sinθ-2cosθ/5cosθ+3sinθ; ⑵(1/4)
已知tan(θ+π/4)=-2,求cosθ平方+sinθcosθ-1
已知sinθ+√3cosθ=2cos(θ-φ),求tanφ.(0
若sinθ+sin^2θ=1,则cos^2θ+cos^4θ+cos^6θ
已知y=2sinθcosθ+sinθ-cosθ(0
2(sinθ+cosθ)= 2√2sin(θ+π/4)为什么?; (-π/2
已知sinθ+cosθ=√2 /3,(0
已知θ∈(-π/2,0),cosθ=13,求sinθ+cos(θ-π/4)的值
化简:[(1+sinθ+cosθ)(sinθ/2-cosθ/2)]/√(2+2cosθ)(0<θ<π)
求证sinθ/(1+cosθ)+(1+cosθ)/sinθ=2/sinθ