[代數] Cosets

看板Math作者 (拿出一張白紙...)時間14年前 (2011/10/30 22:12), 編輯推噓2(206)
留言8則, 3人參與, 最新討論串1/1
1. In the additive group |R^m of vectors, let W be the set of solutions of a system of homogeneous linear equations AX=0. Show that the set of solutions of an inhomogeneous system AX=B is either empty or it is an (additive) coset of W 首先這題的A應該是個方陣吧?! 那麼AX=B無解的話,表示set of solution of AX=B is empty. 若是以這樣的想法,我想不出如果有solution的話,和coset會有甚麼關係..... 2. A group G of order 22 contains elements x and y, where x≠1 and y is not a power of x. Prove that the subgroup generated by these elements in the whole group G. 依照題意我覺得會用到cyclic group,但是不知道從何下手...... 感謝各位大大指教 :) -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 125.225.15.246

10/30 22:54, , 1F
AX=B 有一個解叫做v的話那 v+W都是解
10/30 22:54, 1F

10/30 22:54, , 2F
因為A(v+W)=Av+0=B
10/30 22:54, 2F

10/31 03:44, , 3F
2: |x|=2, 11, 22, for first 2 cases, we have
10/31 03:44, 3F

10/31 03:44, , 4F
G=<x,z> for some z, then y=x^az^b, b=\=0, rewrite
10/31 03:44, 4F

10/31 03:45, , 5F
z by x and y...
10/31 03:45, 5F

10/31 03:46, , 6F
here note that G also equal to <x,z^b> for 2, 11
10/31 03:46, 6F

10/31 03:46, , 7F
are primes.
10/31 03:46, 7F

10/31 11:13, , 8F
感謝以上兩位大大的提示,我在想想看 :D
10/31 11:13, 8F
文章代碼(AID): #1EhLiuRk (Math)