sinπ.cosπ.sin2π.cos2π分别是多少
sinπ.cosπ.sin2π.cos2π分别是多少
sinπ,cosπ,tanπ,sin2π,cos2π ,tan2π的值
cosπ/5*cos2π/5 =(2sinπ/5*cosπ/5*cos2π/5)/(2sinπ/5) =(sin2π/5
若sin(π/4+α)=sinθ+cosθ,2sin^2β=sin2θ,求证:sin2θ+2cos2β=3
已知tan(π/4+α)=2 求(cos2α-sin2α)/(2sinαcosα+cos^2α)
已知sinα+cosα=1/3,α∈(0,π ),那么sin2α,cos2α的值分别为?
α为锐角,且tan(π/4+α)=2,求(sin2αcosα-sinα)/cos2α
sin2(-α)+tan(2π+α)cos2(π+α)-sin(2π-α)cos(π+α)cos2(π+α)化简 求助各
急.设f(θ)=[2cos2θ+sin2(2π-θ)+sin(π/2+θ)-3]/[2+2cos2(π+θ)+cos(-
已知(sin2α)^2+sin2αcosα-cos2α=1,α属于(0,π/2),求sinα,tanα的值
(sin2α)^2+sin2α*cosα-cos2α=1,α∈(0,π/2),求sinα,tanα的值
若2sin(π/4+a)=sinθ+cosθ,2sin^2β=sin2θ,求证sin2a+(1/2)cos2β=0.