已知函数f(x)=2sinxcosx+根号3(2cos^x-1)(1)将函数f(x)化为Asin(wx+f)(w大于0,f的绝对值小于二分之派).(2)求函数f(x)的单调区间

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已知函数f(x)=2sinxcosx+根号3(2cos^x-1)(1)将函数f(x)化为Asin(wx+f)(w大于0,f的绝对值小于二分之派).(2)求函数f(x)的单调区间
已知函数f(x)=2sinxcosx+根号3(2cos^x-1)(1)将函数f(x)化为Asin(wx+f)(w大于0,f的绝对值小于二分之派).(2)求函数f(x)的单调区间

已知函数f(x)=2sinxcosx+根号3(2cos^x-1)(1)将函数f(x)化为Asin(wx+f)(w大于0,f的绝对值小于二分之派).(2)求函数f(x)的单调区间
(1)f(x)=2sinxcosx+√3(cos^2x-1)=sin2x+√3cos2x=2sin(2x+π/3)
(2)由-π/2+2kπ≤2x+π/3≤π/2+2kπ,得,-5π/12+kπ≤x≤π/12+kπ (k是整数)
由π/2+2kπ≤2x+π/3≤3π/2+2kπ,得,π/12+kπ≤x≤7π/12+kπ (k是整数)
故f(x)的单调递增区间是{x|-5π/12+kπ≤x≤π/12+kπ }
单调递减区间是{x|π/12+kπ≤x≤7π/12+kπ} (k是整数)