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Timeline for Invertibility of specific function

Current License: CC BY-SA 4.0

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Nov 4, 2023 at 0:44 comment added Тyma Gaidash See inverse function discussion here or use inverse t function if it is allowed
Oct 13, 2020 at 9:46 history edited Costas Vlachos CC BY-SA 4.0
Added some graphics, in order to better illustrate the problem. Also included a link to my accepted answer in Mathematics Stack Exchange.
Oct 11, 2020 at 22:03 vote accept Costas Vlachos
Oct 9, 2020 at 15:07 comment added Pietro Majer I mean, the two are conjugated by translations, so invertibility in the large is the same problem (but local invertibility at $0$ is not, yes)
Oct 9, 2020 at 13:24 comment added მამუკა ჯიბლაძე @PietroMajer There is a difference: $x-\sin x$ is $x^3/6+O(x^5)$ while $x+\sin x$ is $2x+O(x^3)$
Oct 9, 2020 at 4:14 answer added Timothy Chow timeline score: 13
Oct 9, 2020 at 1:36 answer added Rob Corless timeline score: 8
Oct 7, 2020 at 20:33 comment added Timothy Chow Related: When can an invertible function be inverted in closed form?
Oct 7, 2020 at 18:24 comment added Pietro Majer Note that $$ 2(\varphi-\pi)- \sin (2(\varphi-\pi)) = -\frac{ 4\pi V\left(\varphi\right)^2}{A^2} $$ so what you should probably look for in the literature is the inverse of $u(x):=x\mapsto x-\sin x$ (Or equivalently $x\mapsto x+\sin x$).
Oct 7, 2020 at 17:21 answer added Iosif Pinelis timeline score: 3
Oct 7, 2020 at 14:38 comment added Costas Vlachos @PiyushGrover, thanks for the comment. Yes, I am familiar with the Abel-Ruffini theorem, but I cannot see how it applies to my function, seeing that $V\left(\varphi\right)$ is not a polynomial of degree $n\geq5$. Please forgive me if the link between the Abel-Ruffini theorem and $V\left(\varphi\right)$ is obvious and I just don't see it, as I am not a mathematician.
Oct 7, 2020 at 13:59 comment added Piyush Grover Are you familiar with en.wikipedia.org/wiki/Abel%E2%80%93Ruffini_theorem ?
Oct 7, 2020 at 13:48 review Close votes
Oct 12, 2020 at 3:05
S Oct 7, 2020 at 13:39 history suggested gmvh
Added top-level tag and "closed-form-expressions" tag (since that's what the Q asks for)
Oct 7, 2020 at 13:33 review Suggested edits
S Oct 7, 2020 at 13:39
Oct 7, 2020 at 13:32 review First posts
Oct 7, 2020 at 14:36
Oct 7, 2020 at 13:27 history asked Costas Vlachos CC BY-SA 4.0