最小正周期T=2π/1/2=4π
当sin(1/2x+π/3)=1时有最大值2
1/2x+π/3=2kπ+π/2
1/2x=2kπ+π/6
x=4kπ+π/3
当sin(1/2x+π/3)=-1时有最小值-2
1/2x+π/3=2kπ-π/2
1/2x=2kπ-π5/6
x=4kπ-π5/3