f(x)=ab=-√3/2+√3cos^2ωx-sinωxcosωx
=-√3/2+√3/2(1+cos2ωx)-1/2sin2ωx
=√3/2cos2ωx-1/2sin2ωx
=cos(2ωx+π/6)
因为周期为π,所以ω的值为1