. => 代替內積符號
* =>代替外積符號
//=>代替絕對值
(B.C)(B.C)-(B.B)(C.C)=? ( - /B*C/^2
請給我詳細過程 答案已附上 感謝!
一題向量運算!
2012-04-29 9:01 pm
回答 (1)
2012-04-29 9:28 pm
✔ 最佳答案
(B.C)(B.C)-(B.B)(C.C)= [|B||C|cosΘ]^2 - |B|^2 |C|^2
= |B|^2 |C|^2 [(cosΘ)^2 - 1]
= - |B|^2 |C|^2 [1 - (cosΘ)^2]
= - |B|^2 |C|^2 (sinΘ)^2
= - [|B| |C| (sinΘ)]^2
= - |B * C|^2
收錄日期: 2021-04-26 19:17:41
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120429000015KK03652