Trigonometry

👨🏻‍🏫 學術台數學

[匿名]

2013-05-25 8:06 am

cosx+cos2x+cos3x+...+cos8x=(sin(17x/2)-sin(x/2))/2sin(x/2)

更新1:

Prove*

回答 (1)

Uncle Michael

2013-05-25 8:45 am

✔ 最佳答案

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參考: Uncle Michael

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