满足sin(x - π/4)≥1/2的x的集合是【 】
A、 {x|2kπ+5/12 π≤x≤2kπ+13/12 π,k∈Z}
B、 {x|2kπ-π/12≤x≤2kπ+7/12 π,k∈Z}
C、{x|2kπ+π/6≤x≤2kπ+5/6 π,k∈Z}
D、{x|2kπ≤x≤2kπ+π/6,k∈Z}
满足sin(x - π/4)≥1/2的x的集合是【 】
A、 {x|2kπ+5/12 π≤x≤2kπ+13/12 π,k∈Z}
B、 {x|2kπ-π/12≤x≤2kπ+7/12 π,k∈Z}
C、{x|2kπ+π/6≤x≤2kπ+5/6 π,k∈Z}
D、{x|2kπ≤x≤2kπ+π/6,k∈Z}
A
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