f(x)=√3cos(3x-θ)-sin(3x-θ)是奇函数,则θ等于( )A.kπB.kπ + π/6C.kπ + π/3D.kπ - π/3为什么我算出来的是f(x)=-2sin[3x - (π/3 + θ)]π/3 + θ=周期/2π/3 + θ=kπ/3θ = kπ/3 - π/3...感激不尽啊

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f(x)=√3cos(3x-θ)-sin(3x-θ)是奇函数,则θ等于( )A.kπB.kπ + π/6C.kπ + π/3D.kπ - π/3为什么我算出来的是f(x)=-2sin[3x - (π/3 + θ)]π/3 + θ=周期/2π/3 + θ=kπ/3θ = kπ/3 - π/3...感激不尽啊

f(x)=√3cos(3x-θ)-sin(3x-θ)是奇函数,则θ等于( )A.kπB.kπ + π/6C.kπ + π/3D.kπ - π/3为什么我算出来的是f(x)=-2sin[3x - (π/3 + θ)]π/3 + θ=周期/2π/3 + θ=kπ/3θ = kπ/3 - π/3...感激不尽啊
f(x)=√3cos(3x-θ)-sin(3x-θ)是奇函数,则θ等于( )
A.kπ
B.kπ + π/6
C.kπ + π/3
D.kπ - π/3
为什么我算出来的是f(x)=-2sin[3x - (π/3 + θ)]
π/3 + θ=周期/2
π/3 + θ=kπ/3
θ = kπ/3 - π/3
...
感激不尽啊

f(x)=√3cos(3x-θ)-sin(3x-θ)是奇函数,则θ等于( )A.kπB.kπ + π/6C.kπ + π/3D.kπ - π/3为什么我算出来的是f(x)=-2sin[3x - (π/3 + θ)]π/3 + θ=周期/2π/3 + θ=kπ/3θ = kπ/3 - π/3...感激不尽啊
f(-x)=√3cos(-3x-a)-sin(-3x-a)
=√3cos(3x+a)+sin(3x+a)
=2sin(π/3+3x+a)
-f(x)=-[√3cos(3x-a)-sin(3x-a)]
=-2sin(π/3-3x+a)
=2sin(-π/3+3x-a)
则要该函数是奇函数,f(-x)=-f(x)
2sin(π/3+3x+a)=2sin(-π/3+3x-a)
则π/3+3x+a=2kπ-π/3+3x-a,k∈整数
a=kπ-π/3,k∈整数