@pilko As I understand it from meta.stackexchange.com/a/312594/196432, the Q&A (with positive votes on both question and answers) should not have been deleted. There might be other reasons (and I am purely speculating) that only moderators know about.
> "Destroyed" users have all that, but have all of their posts deleted. It is intended for things like spammers, where we just want them to be gone. A user must have less than 500 reputation in order to be destroyed. Given that, it's up to the moderator to simply select "destroy" from the mod menu.
In any case, the question about $\int\frac{\sqrt{\cos2x}}{\sin x} dx $? seemed interesting to me. So maybe if somebody reposts the question in a better form, it might be useful - and perhaps this one can be merged into it, so that the answers are not lost.
Another option would be to undelete the question - but since it has basically no context other than "I have tried various substitutions", it might get closed and deleted anyway (PSQ/context). And since mods considered the user problematic enough to be destroyed, it's possible that undeleting the post would go against their intentions.
(It's not easy to say, since we do not know the exact reasons why the account was destroyed. But the linked post suggest that this is done only if there are some serious problems with the user.)
So maybe some duplicate closures would be in order. And if the answers to the deleted one add something which is missing in the older duplicates, maybe it can be merged.
It seems quite a lot stuff to be checked (regarding choosing the best duplicate target and also possible merge) - I do apologize, but I won't have time for this right now...
@MartinSleziak thank you for your investigation. I just merged my answer to what appears to be the "main" post. In fact it was more interested by the how and what about community bot rather than the right to exists of this particular post.
@JoséCarlosSantos I was one of those reopen votes. I do not think that there is any benefit to closing a question which is 3 years old. I edited the question a bit to improve it and to make it not a PSQ.
I am a bit less sure whether to add also Example that in general $|abc|\neq |cba|$. (If we ignored the fact that it is proof-verification question, it would be a duplicate.)
Hi @AndrésE.Caicedo - it's quite rare to see you in chat :-)
I hope it's ok that I have edited the dead link in your answer a few days ago - I left a few comments in MO editors' lounge: chat.stackexchange.com/transcript/10243/2019/1/11 (If something more needs to be added regarding this, we can move there.)
@MartinSleziak That's a nice addition. Thanks. I saw your edit to the other post, on proof-verification/"$|abc|\neq |cba|$" and had wondered about closing the currently-closed one as a duplicate of this one. Perhaps it would make more sense now to close the proof-verification one as a duplicate, as it doesn't look like the proof-verification one will be useful to others, while the first question has at least 3 answers (of varying degrees of quality/detail).
To my surprise, I see that the question was reopened.
I am well aware that several users are against editing posts by other users to include context. OTOH in this case the OP is inactive for a long time. There have been many discussions about this on meta, perhaps quid's answer to this one (relatively recent - different topic but related) gives a reasonable summary: Historical lock for preserving old, low quality questions.
