선형대수 이상화 보는중.
![[https]](/wiki/imgs/https.png)
https://www.youtube.com/watch?v=i3VTeQW0Tw4&list=PLSN_PltQeOyjDGSghAf92VhdMBeaLZWR3&index=2
https://www.youtube.com/watch?v=i3VTeQW0Tw4&list=PLSN_PltQeOyjDGSghAf92VhdMBeaLZWR3&index=2Up: 수학,math
GE ¶
ex 1
첫째줄은 그대로 두고,
두째줄은 ②-①×2,
셋째줄은 ③+①
③+② 하면
한편 계수들을 가지고 행렬을 만들면
![$\left[\begin{array}{rrr.r}2&1&1&5\\4&-6&0&-2\\-2&7&2&9\end{array}\right]$](/wiki/cgi-bin/mimetex.cgi?\fs7 \left[\begin{array}{rrr.r}2&1&1&5\\4&-6&0&-2\\-2&7&2&9\end{array}\right] "$\left[\begin{array}{rrr.r}2&1&1&5\\4&-6&0&-2\\-2&7&2&9\end{array}\right]$")
![$\left[\begin{array}{rrr.r}2&1&1&5\\0&-8&-2&-12\\0&8&3&14\end{array}\right]$](/wiki/cgi-bin/mimetex.cgi?\fs7 \left[\begin{array}{rrr.r}2&1&1&5\\0&-8&-2&-12\\0&8&3&14\end{array}\right] "$\left[\begin{array}{rrr.r}2&1&1&5\\0&-8&-2&-12\\0&8&3&14\end{array}\right]$")
![$\left[\begin{array}{rrr.r}2&1&1&5\\0&-8&-2&-12\\0&0&1&2\end{array}\right]$](/wiki/cgi-bin/mimetex.cgi?\fs7 \left[\begin{array}{rrr.r}2&1&1&5\\0&-8&-2&-12\\0&0&1&2\end{array}\right] "$\left[\begin{array}{rrr.r}2&1&1&5\\0&-8&-2&-12\\0&0&1&2\end{array}\right]$")
이 행렬을 upper triangular matrix라고 한다.
이 행렬을 upper triangular matrix라고 한다.
ex 2
![$\left[\begin{array}{rrr.r}1&1&1&a\\2&2&5&b\\4&4&8&c\end{array}\right]$](/wiki/cgi-bin/mimetex.cgi?\fs7 \left[\begin{array}{rrr.r}1&1&1&a\\2&2&5&b\\4&4&8&c\end{array}\right] "$\left[\begin{array}{rrr.r}1&1&1&a\\2&2&5&b\\4&4&8&c\end{array}\right]$")
![$\left[\begin{array}{rrr.r}1&1&1&a\\0&0&3&b-2a\\0&0&4&c-4a\end{array}\right]$](/wiki/cgi-bin/mimetex.cgi?\fs7 \left[\begin{array}{rrr.r}1&1&1&a\\0&0&3&b-2a\\0&0&4&c-4a\end{array}\right] "$\left[\begin{array}{rrr.r}1&1&1&a\\0&0&3&b-2a\\0&0&4&c-4a\end{array}\right]$")
}
}