如題
show that sinxcosnx=sinnxcosx-sin(n-1)x
唔可以用 減=0既方法 sinxcosnx-sinnxcosx+sin(n-1)x=0
唔可以用 砌數方法 sinxcosnx-cosxsinnx+cosxsinnx=sinnxcosx-sin(n-1)x
即係話 我要 sinxcosnx=...=...=...=sinnxcosx-sin(n-1)x
唔該晒大家!!!
Form5 Amaths show that sinxcosnx=sinnxcosx-sin(n-1)x
2008-10-05 10:55 am
回答 (1)
2008-10-05 10:24 pm
收錄日期: 2021-04-23 20:40:53
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081005000051KK00290