sin(2x+π/3)=±1
2x+π/3=kπ+π/2
所以对称轴是x=kπ/2+π/12
sin(2x+π/3)=0
2x+π/3=kπ
x=kπ/2-π/6
所以对称中心是(kπ/2-π/6,0)
sin递增则2kπ-π/2<2x+π/3<2kπ+π/2
kπ-5π/12所以增区间是(kπ-5π/12,kπ+π/12)
同理,减区间是(kπ+π/12,kπ+7π/12)