2sinxcosx=sin2x所以√3sinxcosx=(√3/2)*sin2xcos2x=2(cosx)^2-1所以2(cosx)^2=cos2x+1所以f(x)=(√3/2)sin2x-cos2x+1=√[(√3/2)^2+1^2]*sin(2x+y)+1=√7/2*sin(2x+y)+1其中tany=-1/(√3/2)=-2√3/3所以T=2π/2=π...