點proof sin(a-b)= sina cosb - sinb cosa
點proof cos (a-b)= cosa cosb + sina sinb
點proof sin(a-b)同cos (a-b)
2009-10-08 7:42 pm
回答 (1)
2009-10-08 9:16 pm
收錄日期: 2021-04-21 22:06:04
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091008000051KK00372