Talk:Angle trisection

About trisection of an angle (0-180)
Little help here. I'm in +1. I found how to trisect angle with the Greek tools. Don't know what to do next. Need guidance. E-mail: [redacted]. Rahul2312160 (talk) 16:33, 5 July 2011 (UTC)


 * As the lead of Angle trisection says about the tools allowed by the Greeks: "With such tools, the task of angle trisection is generally impossible". This is a proven result and not just speculation. Either you are using tools they didn't allow (or using them in ways they didn't allow), or your method only works for some specific angles. If you post the method to Reference desk/Mathematics then somebody will probably tell you what is wrong. This talk page is only intended for discussion about how to improve the article. PrimeHunter (talk) 17:19, 5 July 2011 (UTC)


 * Thank you, PrimeHunter, I have posted to the Math reference desk- not looking to be published on a wikipedia page for O.R., just would like someone to refute my simple construction. Wcichello (talk) 14:48, 17 March 2017 (UTC)

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Some angles can be 'trisected'
My understanding, is that certain angles can be constructed (directly or indirectly) and that these angles, where there are multiples of 3, are called trisections. Is this actually an accurate description? To me it appears to be multiple constructions of angles over eachother that could be constructed anyway, the 3-fold factor is incidental rather than intrinsic (albeit deliberate). 92.6.144.20 (talk) 15:38, 6 July 2019 (UTC)

Do we assume the ruler have a width? Is it even relevant?
Could one rotate it about any point or just about where the legs intersect? Alfa-ketosav (talk) 08:38, 19 January 2020 (UTC)

Deletion: "Approximate trisection for angular greater than 0° to 180°"
Hi Joel B. Lewis,

Unfortunately, you deleted my work for the following reason: "Sorry, but this is an enormous amount of detail copied directly from someone's webpage with no proper sourcing at all."

My approach was:

In Commons I worked out a construction description in English with the files I created and inserted this (my) work together with the file into the article.
 * My question, what did I do wrong?
 * What can I do to get my work back into the article?

Best wishes Petrus3743 (talk) 14:44, 16 May 2020 (UTC)


 * The answer is "nothing" for both questions. Being reverted does not mean that you have done something wrong; this means that someone considers that your edit does not improve Wikipedia. For second "nothing", please, read the Wikipedia policy WP:OR. Wikipedia is not the place for your own research. For having a chance for being accepted in Wikipedia, a work should have been published in a notable journal, and been cited in several secondary sources. This is necessary, but not sufficient, as notability is also required. So, it seems that there is no chance that your work could be accepted here. D.Lazard (talk) 15:50, 16 May 2020 (UTC)


 * D.Lazard and Joel B. Lewis,


 * it is not that easy! So please see both this website and only this file without variants, and then tell me what is researched in it?
 * → D. Lazard, was your answer to my second question correct? Petrus3743 (talk) 12:01, 17 May 2020 (UTC)


 * Hi, I agree with D. Lazard. You can read our policy WP:OR to understand what the phrase "original research" means in the Wikipedia context. (It is a kind of local jargon.)  In particular, to include something about this there should be a refereed published paper about it, not just something on some website somewhere.  Separately, you seem to have copied large chunks of the website verbatim; this is both a form of plagiarism and a copyright violation, and Wikipedia certainly cannot accept copied text like that. --JBL (talk) 14:16, 17 May 2020 (UTC)


 * Hi Joel B. Lewis,
 * Now I'm already surprised and concerned about your answer, I think you were wrong about both arguments:
 * "... just something on some website somewhere.": Rouben Rostamian of the University of Maryland, Baltimore County published this really good approximation construction, as described in my work. You shouldn't doubt his raputation and competence!
 * Your claim that I violated copyright law in my post is a serious allegation. I ask you to show me the relevant positions, but please compare beforehand who wrote the text that I copied. I have taken over only one sentence from Rouben Rostamian verbatim (cursive script and marked with reference): Stage 3, corresponding to the steps 8-10 of the construction, produces the angle AOT which, as noted above, is within 1.33 ⋅ 10-16° degrees of the exact trisection. Petrus3743 (talk) 15:26, 17 May 2020 (UTC)
 * Here by "published" you mean "wrote on his personal website". I, too, am a mathematician and have a personal website on which I can write things, but the things I choose to write there are not suitable for inclusion in Wikipedia if they are not appropriately published.  Wikipedia's rules about this are quite clear.  I have struck through my comment about copyright. --JBL (talk) 15:31, 17 May 2020 (UTC)


 * Thanks for your advice, I will remember! By the way, I think it is an important character trait to make an apology if I mistakenly made a serious allegation to a WP colleague. With regards from Munich Petrus3743 (talk) 16:26, 17 May 2020 (UTC)


 * Hi Joel B. Lewis,
 * What is your opinion on this publication (page 6–7)? Would it be possible to include the paragraph "Approximate trisection for angular greater than 0° to 180°" with this reference in the article? Best regards --Petrus3743 (talk) 08:50, 11 July 2020 (UTC)
 * WP:PSTS says "Wikipedia articles should be based on reliable, published secondary sources". Your source is a primary source. It is published is a non-notable journal (see WP:GNG). The article itself and its content are not notable, as there are no secondary sources that refer to them. So, the paragraph that you want to add does not satisfy any criterion allowing its inclusion in Wikipedia. See policies WP:OR and WP:Notability for more details. D.Lazard (talk) 13:28, 11 July 2020 (UTC)

Rearranging images
Can you please explain/justify your recent edits to image positions? What principles are you applying? On my display, after your edits, the page is considerably harder to read because of seemingly haphazard image placement. --JBL (talk) 17:51, 27 January 2021 (UTC)
 * Images have been moved around to avoid overcrowding or collision, which may be a problem if you have narrower screens, hence the addition of the 'Clear' templates for flexible white spaces. Others were rearranged to make better use of the space available. Nerd271 (talk) 17:59, 27 January 2021 (UTC)
 * Images have been moved around to avoid overcrowding or collision, which may be a problem if you have narrower screens, hence the addition of the 'Clear' templates for flexible white spaces. Others were rearranged to make better use of the space available. Nerd271 (talk) 17:59, 27 January 2021 (UTC)

Tomahawk
I have read this several times, and do not understand this explanation. Can someone put in more detail? Jokem (talk) 05:34, 11 April 2021 (UTC)
 * The more detail is already in the linked article Tomahawk (geometry) where it belongs. You did follow the link, right? —David Eppstein (talk) 05:53, 11 April 2021 (UTC)
 * Yes, the link is even more confusing. First, it talks about the apex of the angle, which is A.  To me, the apex is the top, right?  It looks like A is near the bottom.  OK...  Next it says the handle of the tomahawk is touching the apex - A.  It looks to me like the handle is the line crossing C D E.  What touches A does not look like a handle to me.  Would be better if it were animated.  — Preceding unsigned comment added by Jokem (talk • contribs) 21:36, 22 April 2021 (UTC)
 * The apex is the point where the angle is measured. The tip of the handle is placed at that point, as the article says. The description of which pieces of the tomahawk have which names is clearly given in the "description" section of the article. —David Eppstein (talk) 21:54, 22 April 2021 (UTC)

Animation of the construction with a right triangular ruler.
Some times ago, I replaced this animation by its static version for several reasons. The main one was that it was almost impossible to follow and understand the method with it: For improving the description and adding a proof, I had to draw a figure myself, before finding the static figure on commons.

Recently, a link to this animation has been added again. I have reverted it for the other reasons of the former removal: Please, do not link to an animation again, if these issues are not fixed. D.Lazard (talk) 09:20, 21 June 2021 (UTC)
 * This animation is advertising for a specific model of right angle ruler, and, during the display of this ruler, the figure is unreadable.
 * The angle to be trisected is shown only after several steps of the construction, and this is highly confusing.
 * The animation draws a large circle and 3 points on it that are not used for the construction. These are also present in the static figure, but this is much less confusing, because it suffices to not mention them in the description.


 * Hi D.Lazard,
 * it's a shame that my two constructions don't convince you.
 * The set square has no company name, there are many manufacturers. I am not aware of such a narrow interpretation of advertising. Please see Demi-carré, compare this is another one set square.
 * The animation largely follows the original description by Bieberbach.
 * Well, in spite of everything, a team working well together brought the article Dreiteilung des Winkels up to the award Excellent.
 * With so many errors in my constructions, now my suggestion: Replace the static version with your construction, which will surely better match your description and your proof.
 * With your arguments you manage to drive motivated WP employees out of the en.WP ... Greetings--Petrus3743 (talk) 14:35, 21 June 2021 (UTC)
 * "Geodreieck" is the product name of a specific setsquare designed and produced by a German company. So, using an image of a Geodreieck is advertising (and possibly copyvio, as it is unclear how the image has been generated). D.Lazard (talk) 16:48, 21 June 2021 (UTC)


 * Unfortunately, you do not go into factual arguments. I already know that the company ARISTO (Austria, Wörgl) invented the classic Geodreieck®, but as I said above, there are now many manufacturers who produce Geodreieck in very similar designs.
 * Your remark "(and possibly copyvio, as it is unclear how the image has been generated)" is unacceptable. In doing so, you discredit committed WP authors. You are indirectly accusing them of disregarding the license rights and making product advertising in the article Geodreieck. These are very serious allegations. You don't say something like that without evidence!--Petrus3743 (talk) 19:48, 21 June 2021 (UTC)

Perhaps the situation on German wikipedia is irrelevant. A set square or triangle that is popular in the German-speaking world is not always popular in the English-speaking world. In other words, some people may think that ruler and half circle protractor are extra information. I'm not sure what to do with wikidata links.--SilverMatsu (talk) 00:45, 24 June 2021 (UTC)