- 函数y=sin(π/3
- y=sin(π/3-2x)的单调递减区间是
可以直接π/2+2Kπ≤π/3-2x≤3π/2+2Kπ解不等式吗
可是答案是[kπ-1/12π, kπ+5π/12],
我算的是[kπ-1/12π, kπ+7π/12],
答案确保没有错的
- 不行的!
①Y=sin(π/3-2X)=-sin(2X-π/3)
∴Y=sin(2X-π/3)的增区间就是Y=sin(π/3-2X)的减区间
②Y=sin(2X-π/3)的增区间是:
(2kπ-π/2)≦(2X-π/3)≦(2kπ+π/2)
===kπ-π/12≦X≦kπ+5π/12
∴Y=sin(π/3-2X)的单调减区间是:
[kπ-π/12,kπ+5π/12]k∈Z