化简1/sin^2x+1/cos^2x

化简(sin x+cos x-1)(sin x-cos x+1)/sin 2x 化简 1/2cos x-根号3/2sin x 根3sin x+cos x 化简[1-(sin^4x-sin^2cos^2x+cos^4x)/(sin^2)]+3sin^2x cos x/sin x+sin x/(1+cos x) 化简. 2cos x (sin x -cos x)+1 化简[1-(sin^4 x-sin^2 xcos^2 x+cos^4 x)]/(sin^2 x)+3sin^2 x 化简（1)√3sin x+cos x (2）√2(sin x-cos x) （3）√2cos x-√6sin x 化简1/sin^2x+1/cos^2x 化简1—-cos(2X)+sin(2X) 化简 1/2cos x-根号3/2sin x 怎么证明2(1-sin x)(1+cos x)=(1-sin x+cos x)^2 求证（cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2x 化简1+sin x/cos x·sin2x/2cos²（π/4-x/2） 化简：1+sin（x-360度）cos（x-270度）-2cos平方x 化简2sin^2[(π/4)+x]+根号3（sin^x-cos^x）-1 化简sin(2x-pi)sin[x+(3/2)pi]/cos[x+(5/2)pi][1-sin(pi+x)] 已知(1+sin x)/cos x=-1/2,则cos/(sin x-1)=? 求证：tan x/2=sin x/(1+cos x)