函数y=cos(-2x+π/3)的单调减区间是

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函数y=cos(-2x+π/3)的单调减区间是

函数y=cos(-2x+π/3)的单调减区间是
函数y=cos(-2x+π/3)的单调减区间是

函数y=cos(-2x+π/3)的单调减区间是
y=cos(-2x+π/3)=cos(2x-π/3)
递减区间:
2kπ


y=cos(-2x+π/3),
即 y=cos(2x-π/3)
单调减区间:
2kπ≤2x-π/3≤2kπ+π,,k∈Z
∴ 2kπ+π/3≤2x≤2kπ+4π/3,k∈Z
∴ kπ+π/6≤x≤kπ+2π/3,k∈Z
即函数y=cos(-2x+π/3)的单调减区间是 【kπ+π/6,kπ+2π/3】,k∈Z

0+2kπ≤-2x+π/3≤π+2kπ
2kπ-π/3≤-2x≤π+2kπ-π/3
π/6-kπ≥x ≥π/3-kπ