证明tan(3x/2)-tan(x/2)=(2sinx)/(cosx+cos2x)请各位大侠相助!

证明：tan[3x/2]-tan[x/2]=2sinx/[cosx+cos2x] 证明:tan[3x/2]-tan[x/2]=2sinx/[cosx+cos2x] tan(x/2)+sin3x证明是周期函数 证明:(tan^2)x-(sin^2)x=(tan^2)x(sin^2)x 2/tan(x)=3/tan(45-x)怎么解? tan(x/2)+tan(x/3)的周期如何计算? 证明tan^2x-sin^2x=tan^2 sin^2x 证明tan(x+y)+tan(x-y)=sin2x/cos^2x-sin^2y 证明sec x+tanx=tan(π/4 +x/2) 证明tan(3x/2)-tan(x/2)=(2sinx)/(cosx+cos2x)请各位大侠相助! tan^2x + 1/tan^2x = 2(3+cos4x) / (1-cos4x) 证明一下,谢谢了 tan(x/2+ π4)+tan(x/2- π/4)=2tanx证明 tan(x:2+45°)+tan(x:2-45°)=2tanx如何证明. 证明tan(x/2+45°)+tan(x/2-45°)＝2tanx, 证明：tan²x＋1/tan²x＝2（3＋cos4x）／（1-cos4x） 求证tan(x+y)*tan(x-y)=tan^2x-tan^2y/1-tan^2xtan^2y tan(A/x)-1/tan(A/2)=-2/tanA这个怎么证明呢 tan（ x/2+π/4）+tan（x/2-π/4 ）=2tanxtan(x/2+π/4)+tan(x/2-π/4)=[tan(x/2)+tan(π/4)]/[1-tan(x/2)tan(π/4)]+[tan(x/2)-tan(π/4)]/[1+tan(x/2)tan(π/4)]=[tan(x/2)+1]/[1-tan(x/2)]+[tan(x/2)-1]/[1+tan(x/2)]=[(tan(x/2)+1)^2-(tan(x/2)-1)^2]/[1-(tan(x