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化简cos(α-5π/3)+cos(α+13π/3)

题目详情
化简cos(α- 5π/3)+cos(α+13π/3)
▼优质解答
答案和解析
cos(α- 5π/3)+cos(α+13π/3)
=cos(α+2π- 5π/3)+cos(α+13π/3-4π)
=cos(α+ π/3)+cos(α+π/3)
=2cos(α+π/3)