prove the above identities
sin(x/2) = rt [(1-cosx)/2]
cos(x/2) = rt [(1+cosx)/2]
tan(x/2) = sinx/(1+cosx)
a.maths
2008-08-18 2:32 am
回答 (1)
2008-08-18 3:05 am
✔ 最佳答案
Proofs of identities:圖片參考：http://i238.photobucket.com/albums/ff245/chocolate328154/Maths397.jpg?t=1218971126
參考: My Maths Knowledge
收錄日期: 2021-04-23 18:02:26
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