y=sin(-3x+1)的单调增区间
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y=sin(-3x+1)的单调增区间
![y=sin(-3x+1)的单调增区间](/uploads/image/z/18538206-6-6.jpg?t=y%3Dsin%28-3x%2B1%29%E7%9A%84%E5%8D%95%E8%B0%83%E5%A2%9E%E5%8C%BA%E9%97%B4)
先把负号提出来
y=sin(-3x+1)=-sin(3x-1)
所以要求y=sin(-3x+1)的单调增区间,就是求-sin(3x-1)的单调减区间
所以π/2+2kπ<3x-1<3π/2+2kπ
解得:π/6+2kπ/3+1/3<x<π/6+2kπ/3+1/3
所以y=sin(-3x+1)的单调增区间为(π/6+2kπ/3+1/3,π/6+2kπ/3+1/3),k∈整数
y=sin(-3x+1)=-sin(3x-1)
所以要求y=sin(-3x+1)的单调增区间,就是求-sin(3x-1)的单调减区间
所以π/2+2kπ<3x-1<3π/2+2kπ
解得:π/6+2kπ/3+1/3<x<π/6+2kπ/3+1/3
所以y=sin(-3x+1)的单调增区间为(π/6+2kπ/3+1/3,π/6+2kπ/3+1/3),k∈整数