Talk:Cauchy's convergence test

Latest comment: 5 years ago by 76.178.133.207 in topic Untitled

Untitled

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This is of course one of the world's worst tests in practice. Charles Matthews 21:34, 16 January 2006 (UTC)Reply

Actually, I was thinking about writing somewhere in the article that this is only useful for theoretical purposes, like prooving other, more practical criteria AdamSmithee 07:50, 17 January 2006 (UTC)Reply

The test states the obvious. However, it leads to the idea that a series is convergent if it is (per-term) absolutely convergent. Now that is useful, viz, 1-1/2+1/3-1/4 + ...220.244.87.220 (talk) 02:45, 7 August 2012 (UTC)Reply

More importantly: The test guarantees a unique sum. Non-convergent series don't always diverge. Any convergent series, with a unique limit, can be arranged in descending order, and |terms| must tend to zero. Once satisfied, the terms may arranged in any order. Consider 1-1+1-1+1-1 ... . Partial sums are 0,1,0,1,0,... , and it does not converge. Rearrange to (1-1)+(1-1)+, and partial sums are 0,0,0 and is not the same. This is only convergent by Cesaro's sum. 220.244.246.184 (talk) 08:20, 8 August 2012 (UTC)Reply

I think your article is very un-helpful, you do not adequately explain all the important terms and you do not justify why

you use certain formulae. Granted in Textbooks, the publishing house wants as few pages as possible and so explanations and proofs are abbreviated,

but here you have as much room as you need to be clear as can be. Please rewrite what you have written or let someone else write the article. — Preceding unsigned comment added by 76.178.133.207 (talk) 07:58, 13 August 2019 (UTC)Reply

Assessment comment

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The comment(s) below were originally left at Talk:Cauchy's convergence test/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Please add useful comments here--Cronholm144 07:37, 24 May 2007 (UTC) The "if and only if" condition is true only in complete spaces. —Preceding unsigned comment added by 159.149.45.88 (talk) 09:37, 10 February 2009 (UTC)Reply

Last edited at 09:38, 10 February 2009 (UTC). Substituted at 01:51, 5 May 2016 (UTC)