User talk:Usagiop

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Cheers! prime mover (talk) 20:09, 7 May 2022 (UTC)

Preimages
FWIW $f^{-1} \sqbrk U$ as opposed to $\map {f^{-1} } U$ is the preferred notation for preimages. Caliburn (talk) 10:39, 21 May 2022 (UTC)

OK, thanks! Usagiop


 * added that essential note of clarifxion to page in qn --prime mover (talk) 13:45, 21 May 2022 (UTC)

Links with underscores
Please, when implementing an internal link, enter it without underscores. Otherwise it makes maintenance irritatingly more difficult.

Thx for co-ops. --prime mover (talk) 19:38, 21 May 2022 (UTC)

OK. Tanks for a lot of improvements. Usagiop

General structure of definition pages
We have standardised on to use  on all our definition pages.

Is there a solid mathematical reason why at any stage this may not apply? It would make for some complicated reasoning if for any reason does not apply in some circumstances.

And while I am about it, "any" is ambiguous. Defining a quantifier as "for any $A$ in $B$" or whatever could be interpreted to mean "there exists" as well as "for all".

You will find this in our house rules: Help:Editing/House Style/Linguistic Style

There may be discrepancies between how you are used to presenting mathematical arguments and how they are presented in standard style. We take pride on internal consistency of presentation. Hence you may find that if you were to change pages so as to look how you like it, they may well be changed back again.

Thanks for your cooperation. --prime mover (talk) 05:07, 23 May 2022 (UTC)

OK, sorry I just did not know about the convention. I am going to follow the convention. Just to be sure, you are trying to formulate all definitions by, right?

For example, Definition:Embedding (Topology) should be rewritten as follows?


 * $f$ is an embedding (of $A$ into $B$) the restriction $f {\restriction_{A \times f\sqbrk A }}$ of $f$ to its image be a homeomorphism.


 * No, just those that are shaped the way they are shaped. Stuff that's already there does not need to be changed unless it is wrong.

Also thanks for any. OK, I will try to do it better. Usagiop