[理工] [線代]-交大99-資訊聯招

看板Grad-ProbAsk作者 (3百3)時間14年前 (2010/03/14 20:45), 編輯推噓8(8011)
留言19則, 10人參與, 最新討論串3/3 (看更多)
線代觀念題的部份 想問一下 T or F 第4題 b. if A is an m*n matrix, then the nullity of A^t plus the rank of A equals m c. if A is an n*n matrix and has fewer than n disnct eigenvalues, then A is defective d. if A is an n*n matrix, then the rank of A is equal to its nonzero eigenvalues 每一題都想很久... 想請教一下 謝謝!! -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.113.249.123

03/14 20:48, , 1F
b小題顯然為true....考試的時候竟然寫錯了QQ
03/14 20:48, 1F

03/14 20:54, , 2F
個人覺得TFT
03/14 20:54, 2F

03/14 21:00, , 3F
樓上正解
03/14 21:00, 3F

03/14 21:04, , 4F
個人覺得d是F 因該要 A可對角化時才是T
03/14 21:04, 4F

03/14 21:07, , 5F
T F T
03/14 21:07, 5F

03/14 21:07, , 6F
d 前幾天剛好有人討論
03/14 21:07, 6F

03/14 21:08, , 7F
對耶 又想漏了(Jordan form) 謝謝樓上更正
03/14 21:08, 7F

03/14 21:08, , 8F
偷偷問 b小題不是等於n嗎?
03/14 21:08, 8F

03/14 21:12, , 9F
哎呀 是我自己搞錯了 抱歉= =a
03/14 21:12, 9F

03/14 21:14, , 10F
=n 時可對角化沒錯 話說我看成eiganvector說 倒扣了= =
03/14 21:14, 10F

03/14 21:16, , 11F
完全沒想到還有Jordan form..所以d小題是F嗎@@
03/14 21:16, 11F

03/14 21:33, , 12F
TFF?
03/14 21:33, 12F

03/14 21:39, , 13F
TFF 看來我錯了
03/14 21:39, 13F

03/15 02:28, , 14F
嚴格來說d應該是F,要說A之rank與非零的eigenvalue個數
03/15 02:28, 14F

03/15 02:29, , 15F
相同,題目尚未加上non zero eigenvalues之number之字眼
03/15 02:29, 15F

03/15 18:40, , 16F
TFF+1
03/15 18:40, 16F

03/19 23:05, , 17F
樓樓上想多了 跟用詞沒關係 2*2 右上角1其他0 就是反例
03/19 23:05, 17F

03/19 23:14, , 18F
4樓講的是沒錯,但條件不用這麼嚴格,只要eigenvalue 0
03/19 23:14, 18F

03/19 23:14, , 19F
的代數重根數與幾何重根數相等即可
03/19 23:14, 19F
文章代碼(AID): #1BdDg7a_ (Grad-ProbAsk)
文章代碼(AID): #1BdDg7a_ (Grad-ProbAsk)