tan(x)=2求sin(x)cos(x)=?

已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x tan(x)=2求sin(x)cos(x)=? tan x=2,求 sin x * cos x=? 已知:tan x=2 求:sin x+cos x/sin x-cos x=? 1/cos(x) - tan(x) = 3 求sin(x)1/cos(x) - tan(x) = 3求sin(x) sin(180+x)+cos(-x)/sin(180-x)+cos(360+x)=2 求tan(x+45） 求证：tan x/2=sin x/(1+cos x) 求证：1-sin(x)=cos(x)*tan(x/2) 1+cos(2x)/sin(2x)=3/4,求tan(x/2) sin(2x)/1+cos(2x)=3/4,求tan(x/2)的数学题 已知sin(π+x)=-1/2,求cos(2π-x),tan(x-7π) 若tan(x-π)=2,求2sin^2x+1/cos^2x-sin^2x的值若tan(x-π)=2,求2sin^2x+1/cos^2x-sin^2x的值 tan x＝1.5 求sin x 和.cos x tan(x+y)tan(x-y)=sin^2x-sin^2y/cos^2x-sin^2y 顺便问一下. tan,sin,cos是什么意思? 若tanx=2,求:sin(tt/2+x)*cos(tt/2-x)*tan(-x+3tt)/sin(7tt-x)*tan(6tt-x)tt 表示 “派” 求证：(sin x+cos x)(1-tan x)=(2sin x)/(tan2x) 为什么cos(sin(tan x)))=1 已知tan=2 求sin*2x-3sinxcosx-2cos*2x