设f(x)=cos(2x+pai/3)+sinx^

设f(x)=cos(2x+pai/3)+sinx^2-cosx^2+2✔3sinxcosx,求函

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f(x)=根号3 cos^2x+sinxcosx - 根号3/2 =(√3/2)(1+cos2x)+(1/2)sin2x-√3/2 =(√3/2)cos2x+(1/2)sin2x =sin(2x+π/3) (1) 最小正周期T=2π/2=π 单增区间2x+π/3∈[2kπ-π/2,2kπ+π/2] 即x∈[kπ-5π/12,kπ+π/12] (2) x∈[0,3π] 2x+π/3∈[π/3,6π+π/3] 满足...