-2kπ-π/2≤(π/3)-2x≤-2kπ+π/2
2kπ-π/2≤2x+π/3≤2kπ+π/2
2kπ-5π/6≤2x≤2kπ+π/6
kπ-5π/12≤x≤kπ+π/12