f（x）=2√3sinxcosx-2cos^2 x+1.=√3sin2x -cos2x=2(√3/2sin2x -1/2 cos2x)=2(sin2xcosπ/6-cos2xsinπ/6)=2sin(2x-π/6)∴最小正周期T=2π/2=πf(a)=2sin(2a-π/6)=1sin(2a-π/6)=1/22a-π/6=2kπ+π/6 或2a-π/6...