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问题: 求函数周期

y=sin(x+Π/3)sin(x+Π/2)的最小正周期为多少?请详细解答"谢谢

解答:

y=sin(x+π/3)sin(x+π/2)
=sin(x+π/3)(sinxcosπ/2+cosxsinπ/2)
=sin(x+π/3)cosx
=(sinxcosπ/3+cosxsinπ/3)cosx
=1/2sinxcosx+二分之根号三倍的(cosx的平方)不好意思
=1/4sin2x+√3(cos2x+1)/4
=1/2(1/2sin2x+√3/2cos2x)+√3/4
=1/2sin(2x+π/3)+√3/4
∴T=2π/2=π
∴最小正周期为π