已知函数f(x)=cos^2(x+π/12)+1/2sin2x求f(x)的最值求f(x)的单调增区间另外,想问这个变换是怎么来的,为什么2乘进(x+π/12)之后,整个cos还要除于2:cos^2(x+π/12)=[cos(x+(π/12)]^2=[cos(2x+(π/6))+1]/2
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已知函数f(x)=cos^2(x+π/12)+1/2sin2x求f(x)的最值求f(x)的单调增区间另外,想问这个变换是怎么来的,为什么2乘进(x+π/12)之后,整个cos还要除于2:cos^2(x+π/12)=[cos(x+(π/12)]^2=[cos(2x+(π/6))+1]/2
已知函数f(x)=cos^2(x+π/12)+1/2sin2x
求f(x)的最值
求f(x)的单调增区间
另外,想问这个变换是怎么来的,为什么2乘进(x+π/12)之后,整个cos还要除于2:cos^2(x+π/12)=[cos(x+(π/12)]^2=[cos(2x+(π/6))+1]/2
已知函数f(x)=cos^2(x+π/12)+1/2sin2x求f(x)的最值求f(x)的单调增区间另外,想问这个变换是怎么来的,为什么2乘进(x+π/12)之后,整个cos还要除于2:cos^2(x+π/12)=[cos(x+(π/12)]^2=[cos(2x+(π/6))+1]/2
这是利用公式 cos2x=2(cosx)^2-1 (cosx)^2=1/2(cos2x+1)
f(x) = 1/2 cos(2x+pi/6), g(x) = 1+ 1/2 sin2x
f(x) 对称轴为2x+pi/6 = 0, 2pi, ...
x = -pi/12 +/- npi...
f(x)+g(x) = 1/2 cos2x * sqrt(3)/2 - 1/2 sin2x * 1/2 + 1 + 1/2 sin2x
= 1/2 cos2x sqrt(3...
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f(x) = 1/2 cos(2x+pi/6), g(x) = 1+ 1/2 sin2x
f(x) 对称轴为2x+pi/6 = 0, 2pi, ...
x = -pi/12 +/- npi...
f(x)+g(x) = 1/2 cos2x * sqrt(3)/2 - 1/2 sin2x * 1/2 + 1 + 1/2 sin2x
= 1/2 cos2x sqrt(3)/2 + 1/2 sin2x 1/2 + 1 = 1/2 cos(2x-pi/6) + 1
最小正周期派,值域[-1/2, 3/2]
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