y＝√3sinxcosx+cos²x
＝(√3/2)sin2x+(1+cos2x)/2
＝1/2+[(sin2x·(√3/2)+cos2x·(1/2)]
＝1/2+(sin2xcos30°+cos2xsin30°)
＝1/2+sin(2x+30°).
∴sin(2x+30°)＝1时,y|max＝3/2;
sin(2x+30°)＝-1时,y|min＝1/2.
最小正周期：T＝2π/2＝π.