已知函数f(x)=2sin^2(帕/4+x)-根号3cos2x,x属于R
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f(x)=1-cos(π/2+2x) -√3cos2x
=2[(1/2)sin2x-(√3/2)cos2x]+1
=2sin(2x-π/3)+1
(1)令 -π/2+2kπ≤2x-π/3≤π/2+2kπ
解得-π/12+kπ≤x≤5π/12+kπ
f(x)单调递增区间为[-π/12+kπ,5π/12+kπ],k∈Z
(2)由(1)易得,f(x) 在[π/4,5π/12]上是增函数,在[5π/12,π/2]上是减函数,
当x=5π/12时,f(x)取最大值为2+1=3,当x=π/4时,f(x)取最小值为2×(1/2)+1=2
=2[(1/2)sin2x-(√3/2)cos2x]+1
=2sin(2x-π/3)+1
(1)令 -π/2+2kπ≤2x-π/3≤π/2+2kπ
解得-π/12+kπ≤x≤5π/12+kπ
f(x)单调递增区间为[-π/12+kπ,5π/12+kπ],k∈Z
(2)由(1)易得,f(x) 在[π/4,5π/12]上是增函数,在[5π/12,π/2]上是减函数,
当x=5π/12时,f(x)取最大值为2+1=3,当x=π/4时,f(x)取最小值为2×(1/2)+1=2
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