y=sinxcosx+根号3cos*2x
=1/2sin2x+√3/2(1+cos2x)
=1/2sin2x+√3/2cos2x+√3/2
=sin(2x+π/3)+√3/2
T=2π/2=π
图象的两条相邻对称轴的距离d=半个周期
d=π/2