sinx-1)/cosx怎么化成[sin(x/2)-cos(x/2)]/[cos(x/2)+sin(x/2
化简sin^4x/sinx-cosx - (sinx+cosx)cos^2x/tan^2x-1
若|sinx|>|cosx|,则sin^2 x>cos^2 x
求化简(sinx+tanx)/cos^2x+sin^2x+cosx
证明成立:[cos(3x)-sin(3x)]/(cosx+sinx)=1-2sin(2x).
Sin^x怎么变化成 1-cos(2x) /2
sinx+cosx/sinx-cosx=2 求sinx/cos^3x +cosx/sin^3x
证明x∈(0,π/2),cos(cosx)>sin(sinx)
(1+2sinxcosx+cos^2x-sin^2x)+1这个是怎么到这步的[(cosx+sinx)(cosx+sinx
f(x)=2cos*sin(x+π/3)-^3sin^2x+sinx*cosx
求证:Sin^2 x / (sinx-cosx) - (sin x + cos x)/(ta
已知(sinx+cosx)/(cosx-sinx)=2,则2sin²x-sinxcosx+cos²x
请问怎么证明sinX+sin(X+Y)+sin(X+2Y)/cosX+cos(X+Y)+cos(X+2Y)=tan(X+