[理工] [線代]四大空間

看板Grad-ProbAsk作者 (電磁霸主)時間12年前 (2011/12/26 22:31), 編輯推噓6(6推 0噓 8→)
留言14則, 9人參與, 最新討論串1/1
⊥ Let A be a 7x5 matrix of rank 4. What is the dimension of N(A) . 解: ⊥ dim N(A) = 7-dim col(A) = 3 爲什麼是用7去減而不是用5呢 ? -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 111.249.139.64
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12/26 22:36, , 1F
用5減去的是Dim N(A) 維度定理dim N(A) + rank(A) = 5
12/26 22:36, 1F
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12/26 22:37, , 2F
我比較好奇的是N(A)per = Row(A) 不是應該等於4嗎0.0 '
12/26 22:37, 2F
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12/26 22:38, , 3F
dim N(A)per = rank(A) = dim row(A) = dim col(A)
12/26 22:38, 3F
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12/26 22:38, , 4F
二三行請忽略 ...有人可以幫解釋嗎 = = 感覺腦筋打結
12/26 22:38, 4F
推
12/26 23:15, , 5F
答案應該是4 解答那個解法是dim(N(A^t))吧
12/26 23:15, 5F
推
12/26 23:35, , 6F
我也覺得是4
12/26 23:35, 6F
推
12/26 23:38, , 7F
推五樓 ..我也覺得答案問的是dim N(A^t)才是4
12/26 23:38, 7F
推
12/26 23:48, , 8F
N(A)per = R(A^t) = R(A) = 4
12/26 23:48, 8F
推
12/26 23:51, , 9F
答案是4才對
12/26 23:51, 9F
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12/27 23:36, , 10F
爲什麼是4，小的資質駑鈍..煩請講解..
12/27 23:36, 10F
推
12/27 23:39, , 11F
二樓已經說啦~
12/27 23:39, 11F
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12/27 23:41, , 12F
dim N(A)per = dim Row(A)=rank(A)
12/27 23:41, 12F
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12/27 23:45, , 13F
ok，懂囉，原來這麼簡單..被詳解誤了..
12/27 23:45, 13F
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09/11 14:41, , 14F
ok，懂囉，原來這麼簡 https://daxiv.com
09/11 14:41, 14F
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