Re: [代數] 自由群的問題
※ 引述《hotplushot (熱加熱)》之銘言：
: A nonzero free abelian group has a subgroup of index n
: for all positive integer n.
: 這題毫無頭緒.....
: 可否請版友協助
: 感謝!!!!
because F is free abelian
F=Z⊕...⊕Z(m個)
let A=Z⊕...⊕nZ⊕...⊕Z
[F:A]=n
and nZ is subgroup of Z
so conclusion is hold.
是這樣嗎
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◆ From: 111.252.210.30
※ 編輯: hotplushot 來自: 111.252.210.30 (03/18 01:04)
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