设f(x)=6cos^2x-根号3sin2x,求f(x)的单调增区间和单调减区间

问题描述:

设f(x)=6cos^2x-根号3sin2x,求f(x)的单调增区间和单调减区间

f(x)=6cos^2x-根号3sin2x
=3+3cos2x-√3sin2x
=3+2√3cos(2x+π/6),
它的减区间由2kπ