請問圖中之題的（b）（c），如何計算出才能得到答案?
回答 (1)
2020-06-23 9:54 am
一般,
a = a1 i + a2 j + a3 k = (a1,a2,a3),
b = b1 i + b2 j + b3 k = (b1,b2,b3)
則
a×b = (a2×b3-a3×b2)i-(a1×b3-a3×b1)j+(a1×b2-a2×b1)k
= (a2×b3-a3×b2, -(a1×b3-a3×b1), a1×b2-a2×b1)
a = a1 i + a2 j + a3 k = (a1,a2,a3),
b = b1 i + b2 j + b3 k = (b1,b2,b3)
則
a×b = (a2×b3-a3×b2)i-(a1×b3-a3×b1)j+(a1×b2-a2×b1)k
= (a2×b3-a3×b2, -(a1×b3-a3×b1), a1×b2-a2×b1)
收錄日期: 2021-05-04 02:28:37
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20200623001026AALtfxu