函数y=2sin ([π/3−2x)=-2sin(2x-
π
3]),即求 sin(2x-[π/3]) 减区间.
由 2kπ+[π/2]≤2x-[π/3]≤2kπ+[3π/2],k∈z,
求得kπ+
5π
12≤ x ≤ kπ+
11π
12,即kπ−
7π
12≤ x ≤ kπ−
π
12,k∈z,
故选 B.
函数y=2sin ([π/3−2x)=-2sin(2x-
π
3]),即求 sin(2x-[π/3]) 减区间.
由 2kπ+[π/2]≤2x-[π/3]≤2kπ+[3π/2],k∈z,
求得kπ+
5π
12≤ x ≤ kπ+
11π
12,即kπ−
7π
12≤ x ≤ kπ−
π
12,k∈z,
故选 B.