求函数单调减区间y=sin1/2xcos1/2x+根号3 cos^2 1/2x +1的 单调减区间!

y=sin(1/2x)cos(1/2x)+√3cos^2(1/2x)+1
=1/2sinx+√3/2(1+cosx)+1
=sin(x+π/3)+ √3/2+1
π/2+2kπ