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)