如何证明tan x/2 =sin/(1+cosx)=(1-cosx)/sinx哪位大哥给算出来呀

证明:(tan^2)x-(sin^2)x=(tan^2)x(sin^2)x 证明tan^2x-sin^2x=tan^2 sin^2x 证明tan^2x=2*tan^2y+1,求证sin^2y=2sin^2x-1 如何证明tan x/2 =sin/(1+cosx)=(1-cosx)/sinx哪位大哥给算出来呀 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 初三或者高中证明题,tan sin cos的东东证明,tan(X/2)=(1-cosX)/sinX sin(2x) = (2*tan(x))/(1+tan(x)^2)有这个公式吗?求证明 证明1/sin^x+1/cos^2x-1/tanx^2x=2+tan^2 证明(1-2sin x cos x )/(cos^2x-sin^2x)=(1-tan x)/(1+tan x)谢谢谢谢 急 证明tan(x+y)+tan(x-y)=sin2x/cos^2x-sin^2y tan a/2=(1-cos a)/sin a=sin a/(1+cos a)如何证明? 证明 (tan xsin x)/(tan x-sin x)-(1+cos x)/sin x上面打错了 (tan xsin x)/(tan x-sin x)=(1+cos x)/sin x 这道证明题如何做?1.己知tanα²=2tanβ²+1 求证:sin ²β=2sin²α-1 sinπ(x-1)=-sinπx如何证明 证明tan^2x-sin^2x=tan^2x*sin^2x解sin^2x sin^2x--------- - -----------cos^2x 1等于sin^2x sin^2x--------- - -----------cos^2c cos^2x+sin^2x接下来还能做吗?这道题还有其他证法吗?怎么能等式两边同除呢？这是证明题，证 证明tanα/2=1-cosɑ/sinɑ 证明tan a/2=sin a/(1+cos a) 1-(sin^6x+cos^6x)=3sin^2xcos^2x 如何证明?