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函数y=sinxsin(3π/2-x)的最小正周期是

题目详情
函数y=sin xsin(3π/2-x)的最小正周期是
▼优质解答
答案和解析
y=sin xsin(3π/2-x)
=sinx(sin2π/3cosx-cos2π/3sinx)
=√3/2sinxcosx+1/2(sinx)^2
=√3/4*sin2x+1/4(1-cos2x)
=√3/4*sin2x-1/4*cos2x+1/4
=1/2(√3/2sin2x-1/2*cos2x)+1/4
=1/2sin(2x-π/6)+1/4
最小正周期T=2π/2=π