a= 3i + 4j +5k
b= 2i + 2j + 3k
c= 6i -7j -8k
If d= 7i + 23j + 29k, find x,y,z so that d = xa + yb + zc
[applied maths] vector
2008-09-15 1:53 am
回答 (1)
2008-09-15 2:57 am
✔ 最佳答案
d = xa + yb + zc 7i + 23j + 29k=x(3i + 4j +5k)+y(2i + 2j + 3k)+z(6i -7j -8k)
7i + 23j + 29k=(3x+2y+6z)i +(4x+2y-7z)j+(5x+3y-8z)k
So
3x+2y+6z=7
4x+2y-7z=23
5x+3y-8z=29
Using Gauss elimination, we have x=3,y=2,z=-1
收錄日期: 2021-04-26 13:04:47
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080914000051KK01777