y=sin(π／3-x ）=-sin(x-π/3)
求原函数的增区间,即求y=sin(x-π/3)的减区间
∴ 2kπ+π/2≤x-π/3≤2kπ+3π/2
即 2kπ+5π/6≤x≤2kπ+11π/6
∴ 单调递增区间是【2kπ+5π/6,2kπ+11π/6】,k∈Z