求证:(sin x+cos x)(1-tan x)=(2sin x)/(tan2x)
求证(tanxtan2x/tan2x-tanx)/(tan2x-tanx)+√3(sin^2x-cos^2x)=2sin
已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x
证明(1-2sin x cos x )/(cos^2x-sin^2x)=(1-tan x)/(1+tan x)
求证 (1—tan^2X)/(1+tan^2X)=cos^2X—sin^2X
(cos^2 2x-sin^2 2x)/(1-tan2x)=(1+2sin2xcos2x)/(1+tan2x)
证明1-tan^2x/1+tan^2x=cos^2x-sin^2x
求证(cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2
求证 1+2sin x cos x ———————— cos ︿2—sin x︿2 =1+tan
证明 (tan xsin x)/(tan x-sin x)-(1+cos x)/sin x
求证 tan(2π-X)sin(-2π-X)cos(6π-X)/ sin(X+3π/2)*cos(X+3π/2)=-ta
求证 cos^8(x)-sin^8(x)=cos2x【1-1/2sin^2(2x)】
三角等式求证:cos^6x+sin^6x=1-3sin^2x+3sin^4x