tanθ=2,则［〔sin π/4+θ〕/〔sin π/4-θ〕］*tan2θ=?

tanθ=2,则［〔sin π/4+θ〕/〔sin π/4-θ〕］*tan2θ=? 求证2(cosθ -sinθ )/1+sinθ +cosθ =tan(π/4-θ /2)-tanθ /2 log(tanθ+cotθ)sinθ=-1/4,θ∈(0,π／2),则log(tanθ)sinθ=?需要过程.谢谢. tan（π/4-θ）=1/2,则sinθcosθ= 若sinθ+2cosθ=更号5则tan(θ+π/4)= tan(θ/2）=-1/3,则sin[θ+(π/4)]=? 证明tan^θ-sin^2θ=tan^2θsin^2θ证明（1）tan^θ-sin^2θ=tan^2θsin^2θ（2）sin^4x+cos^4x=1-2sin^2cos^2x（31-tan^2x/1+tan^2x=cos^2x-sin^2x 求证：2（cos θ -sin θ )/(1+sinθ +cosθ)=tan(∏/4- θ /2)-tan(θ /2) 已知2tanθ/1+tan^2θ=3/5,求sin^2(π/4+θ) tan(a+π/4)=2,则cos2a+3sin^2a+tan a= 求证tan^2θ-sin^2θ=tan^2θsin^2θ 已知tanθ=a(a>1),求sin(π/4+θ)/sin(π/2-θ)×tan2θ的值 已知tanθ=2则sinθ+sinθcosθ-2cosθ=? tanθ=a,求[sin(pi/4+θ)/sin(pi/2-θ)]*tan2θ tanθ=a,求[sin(pi/4+θ)/sin(pi/2-θ)]*tan2θ, 若θ为第二象限角,则sinθ/|sinθ|+√1-sin^2θ/|cosθ|+tanθ/|tanθ|+cotθ/|cotθ|= 求证 tanθ(1+sinθ )+sinθ /tanθ (1+sinθ )-sinθ =tanθ+sinθ/tanθsinθ 已知tan(θ+π/4)=-2,求cosθ平方+sinθcosθ-1