唔該..有邊個可以計個步驟同個ans比我睇？
prove the following identities
sec^2 θ csc^2 θ = sec^2 θ+scs^2 θ
有誰可以幫我計這題數？
2008-11-14 5:08 am
回答 (1)
2008-11-23 5:33 am
✔ 最佳答案
Prove : sin4x + cos4x = 1 - 2 sin2x cos2xLHS = sin4x + cos4x
= sin4x + 2 sin2x cos2x + cos4x - 2 sin2x cos2x
= (sin2x + cos2x)2 - 2 sin2x cos2x
= (1)2 - 2 sin2x cos2x
= 1 - 2 sin2x cos2x
= RHS
參考: me
收錄日期: 2021-04-23 15:21:42
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081113000051KK01262