已知函数f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3(x∈R)求f(x)的最小正周期?

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已知函数f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3(x∈R)求f(x)的最小正周期?

已知函数f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3(x∈R)求f(x)的最小正周期?
已知函数f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3(x∈R)求f(x)的最小正周期?

已知函数f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3(x∈R)求f(x)的最小正周期?
f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3
=sinxcosx-√3cos²x+√3/2
=(1/2)sin2x-(√3/2)(2cos²x-1)
=(1/2)sin2x-(√3/2)cos2x
=sin(2x-π/3)
所以最小正周期T=2π/2=π

f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3
=sin(x)cos(x)-√3cos²(x)+1/2√3
=(1/2)sin(2x)-(1/2)√3(1+cos2x)+1/2√3
=(1/2)sin(2x)-[(√3)/2]cos(2x)
=sin(2x)cos(π/3)-cos(2x)sin(π/3)
=sin(2x-π/3)
最小正周期为2π/2=π

f(x)=sin(x)sin(x+π/2)-√3cos²(3π+x)+1/2√3=1/2(sin2x)-√3cos²x+1/2√3
=1/2(sin2x)-√3/2* (2 cos²x-1)-√3/2+1/2√3
最小正周期T=π

最小正周期T=π。