作者king31815 (口八押係)
站內Math
標題[分析] 兩題跟uniformly continuous有關的題目
時間Fri Oct 1 23:09:25 2010
這是我在zygmund實分析的第一章看到的題目
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1. If f is defined and uniformly continuous on E, show there is a function f
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defined and continuous on E(closure) such that f=f on E.
2. If f is defined and uniformly continuous on a bounded set E, show that f
is bounded on E.
這兩題我在rudin跟apostol上都有看到類似的習題,但是卻都是跟R^n空間有關,像是第一
題的codomain就是在R上,而第二題的domain是在R^n上,所以一個可以利用完備性,一個
可以利用Heine-Borel thm,就可以解決,所以也令我懷疑這兩題的命題是否有錯。
想麻煩高手為我解答了~拜託~
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◆ From: 124.8.9.175
推 zombiea :use uniformly conti. sends chauchy seq to chauchy 10/01 23:33
→ king31815 :but I can not sure the limit existence... 10/01 23:37
推 lwei781 :1.f(x) = x, domain 取[0,1] 交 Q, Range 取Q 10/02 11:15
推 lwei781 :closure of E 當成是[0,1] in R with usualy metric 10/02 11:17
→ lwei781 :how to extend this? 10/02 11:18