已知函数f(x)=2cosxsin(x+π/3)-根号3sin^2x+sinxcosx+2(x∈R),1,求函数f(x)的最小正周_数学解答

已知函数f(x)=2cosxsin(x+π/3)-根号3sin^2x+sinxcosx+2(x∈R),
1,求函数f(x)的最小正周期和单调增区间；

人气：465 ℃　时间：2019-08-19 12:06:35

解答

f(x)=sinxcosx+sqrt(3)(cosx)^2-sqrt(3)(sinx)^2+sinxcosx+2
=2sinxcosx+sqrt(3)[(cosx)^2-(sinx)^2]
=sin2x+sqrt(3)cos2x
=2sin(2x+π/3)
所以最小正周期是π
单调增区间[-5π/12+kπ,π/12+kπ],k是整数.