[數撚圍爐區] abc conjecture is still a conjecture (3)

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11 Like 1 Dislike
2018-10-20 13:34:49
\mathbb{R} is uncountable 應該係given架啦
所以你個任務係證 F_n is countable for all n
2018-10-20 13:37:04
cantor set算不算closed set containing no nonempty open interval🤔
2018-10-20 13:42:47
係, 佢係totally disconnected
咦我好似 諗錯左D野
果然無紙無筆齋諗會出事
2018-10-20 14:04:41
依個係Abbott本嘢教prove Baire's Theorem嘅其中一題
2018-10-20 14:15:22
咦我唔記得左呢條theorem, 太耐無用過
F_n is nowhere dense, 完
2018-10-20 14:19:10
如果我同你講,依條題目喺nowhere dense set依個section之前呢
2018-10-20 14:19:11
2018-10-20 14:23:46
你可以證左 R\F_n 係dense open set, 之後用 Theorem 3.5.2.
2018-10-20 14:25:34
一言驚醒洛克人
唔該晒
2018-10-20 14:37:26
屌我連咁簡單ge野都諗錯我無地自容
2018-10-20 14:40:20
乖,你好叻
我先蠢
2018-10-20 14:43:11
2018-10-20 16:46:40
2018-10-20 17:13:19
Given a countable set A = {a_1, a_2, a_3, …}, define f(a_n) = 1/n and f(x) = 0 for all x ∉ A. Find D_f

The set of discontinuity = A 定 {a_1} 定其他? a_n 嘅分佈會影響個continuouity?
2018-10-20 17:31:47
就係A\{subsequential limitof A}
2018-10-20 18:02:18
thx
2018-10-20 18:09:39
你要識證喎
2018-10-20 18:13:05
prove f is continuous for subsequential limit of A?
2018-10-21 13:01:35
2018-10-21 13:02:03
2018-10-21 14:14:02
2018-10-21 14:28:02
2018-10-21 14:29:25
2018-10-21 14:36:35
2018-10-22 22:39:01
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