求f(x)=3sin(-2x+π/3)的单调区间

求f(x)=3sin(-2x+π/3)的单调区间
求f(x)=3sin(-2x+π/3)的单调区间

求f(x)=3sin(-2x+π/3)的单调区间
f(x)=-3sin(2x-π/3)
所以和sin(2x-π/3)单调性相反
sinx增区间是(2kπ-π/2,2kπ+π/2)
所以此处即2kπ-π/2<2x-π/3<2kπ+π/2
2kπ-π/6<2x<2kπ+5π/6
kπ-π/12sinx减区间是(2kπ+π/2,2kπ+3π/2)
同理,这里是kπ+5π/12所以f(x)的增区间是(kπ+5π/12,kπ+11π/12)
减区间是(kπ-π/12,kπ+5π/12)