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=? 求极限：sin x^tan x(x→π/2) 1/cos(x) - tan(x) = 3 求sin(x)1/cos(x) - tan(x) = 3求sin(x) 证明:(tan^2)x-(sin^2)x=(tan^2)x(sin^2)x 求证tan^x-sin^2x=tan^2x*sin^2x sin(180+x)+cos(-x)/sin(180-x)+cos(360+x)=2 求tan(x+45） 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 tan²x=2tan²β+1 求cos2x+sin²β=? 证明tan^2x-sin^2x=tan^2 sin^2x 求∫1／tan^2x+sin^2x dx 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” sin(2x) = (2*tan(x))/(1+tan(x)^2)有这个公式吗?求证明 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)