化简：(1tanθ2−tanθ2)2•(1−2tanθ•1tan2θ)=．

Question

化简：((1)/(tan(θ)/(2))−tan(θ)/(2))2•(1−2tanθ•(1)/(tan2θ))=______．

Answer 1

(1tanθ2−tanθ2)2•(1−2tanθ•1tan2θ)=(cosθ2sinθ2−sinθ2cosθ2)2•(1−2sinθcosθ•cos2θsin2θ) =(2cosθsinθ)2(1−cos2θcos2θ)=4cos2θsin2θ×cos2θ−(cos2θ−sin2θ ) cos2θ=4...