设函数f(x)=(sinωx+cosωx)^ 2+2cos^2 ωx(ω>0)的最小正周期为2π/3(1)求ω的最小正周期.(2)若函数y=g(x)的图像是由y=f(x)的图像向右平移π/2个单位长度得到,求y=g(x)的单调增区间
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设函数f(x)=(sinωx+cosωx)^ 2+2cos^2 ωx(ω>0)的最小正周期为2π/3(1)求ω的最小正周期.(2)若函数y=g(x)的图像是由y=f(x)的图像向右平移π/2个单位长度得到,求y=g(x)的单调增区间
设函数f(x)=(sinωx+cosωx)^ 2+2cos^2 ωx(ω>0)的最小正周期为2π/3
(1)求ω的最小正周期.(2)若函数y=g(x)的图像是由y=f(x)的图像向右平移π/2个单位长度得到,求y=g(x)的单调增区间
设函数f(x)=(sinωx+cosωx)^ 2+2cos^2 ωx(ω>0)的最小正周期为2π/3(1)求ω的最小正周期.(2)若函数y=g(x)的图像是由y=f(x)的图像向右平移π/2个单位长度得到,求y=g(x)的单调增区间
(1)f(x)=sin²ωx+cos²ωx+2sinωxcosωx+2cos²ωx=1+2sinωxcosωx+2cos²ωx
=2+2sinωxcosωx+(2cos²ωx-1)=sin2ωx+cos2ωx+2=√2sin(2ωx+π/4)+2
最小正周期T=2π/2ω=π/ω=2π/3 ,所以ω=3/2,f(x)=√2sin(3x+π/4)+2
(2)将f(x)的图像向右平移π/2个单位长度即得y=g(x),
所以g(x)=f(x-π/2)=√2sin(3x-3π/2+π/4)=√2sin(3x-5π/4)+2
当-π/2+2kπ ≤ 3x-5π/4 ≤ π/2+2kπ时g(x)单调递增
解不等式得π/4 +2kπ/3 ≤ x ≤ 7π/12 +2kπ/3
则y=g(x)的单调增区间为[ π/4 +2kπ/3,7π/12 +2kπ/3 ]
f(x)=(sinωx+cosωx)^ 2+2cos^2 ωx=1+2sinωxcosωx+2cos^2ωx
=1+2cosωx(sinωx+cosωx)=1+2√2cosωxsin(ωx+π/4)
=1+√2[sin(2ωx+π/4)+sinπ/4]
=1+√2sin(2ωx+π/4)+1
=√2sin(2ωx+π/4)+2
最小正周期为2π/3 ,T=2...
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f(x)=(sinωx+cosωx)^ 2+2cos^2 ωx=1+2sinωxcosωx+2cos^2ωx
=1+2cosωx(sinωx+cosωx)=1+2√2cosωxsin(ωx+π/4)
=1+√2[sin(2ωx+π/4)+sinπ/4]
=1+√2sin(2ωx+π/4)+1
=√2sin(2ωx+π/4)+2
最小正周期为2π/3 ,T=2π/2ω=π/ω=2π/3,
(1),ω=3/2
(2),g(x)=√2sin[3(x-π/2)+π/4]+2
=√2sin(3x-5π/4)+2
y=g(x)递增区间为2kπ-π/2<3x-3π/4<2kπ+π/2
2kπ/3+π/12
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1 fx=√2sin2ωx+π/4+2 所以ω=3/2
2 fx=√2sin3x+π/4+2 所以gx=√2sin[3x-π/2+π/4]+2=√2sin3x-5π/4+2 因为3x-5π/4在[2kπ-π/2,2kπ+π/2]k属于Z 上递增 所以gx在[2kπ/3+3π/12,2kπ/3+7π/12]k属于Z 上递增 因为3x-5π/4在[2kπ+π/2,2kπ+3π/2]k属于Z 上递减 所以3x-5π/4在[2kπ/3+7π...