Timeline for Conjectute: no exist an equilateral triangle such that all vertices are integer numbers [closed]
Current License: CC BY-SA 3.0
18 events
| when toggle format | what | by | license | comment | |
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| Oct 27, 2017 at 17:11 | comment | added | LSpice | @VaughnClimenhaga, can't you just use the same visual proof directly on the equilateral triangle itself? | |
| Mar 21, 2016 at 12:52 | vote | accept | Oai Thanh Đào | ||
| Mar 19, 2016 at 16:37 | review | Reopen votes | |||
| Mar 19, 2016 at 19:58 | |||||
| Mar 19, 2016 at 16:19 | history | edited | Oai Thanh Đào | CC BY-SA 3.0 |
deleted 20 characters in body; edited tags
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| Mar 19, 2016 at 16:19 | comment | added | Vaughn Climenhaga | My favorite proof of this is to observe that if you can do it with an equilateral triangle, then by a few reflections you can do it with a regular hexagon, and then there's a nice visual proof that a regular hexagon cannot be put on the integer lattice: mathoverflow.net/a/25305/5701 | |
| Mar 19, 2016 at 16:15 | history | closed |
Loïc Teyssier José Figueroa-O'Farrill Qiaochu Yuan Douglas Zare Emil Jeřábek |
Not suitable for this site | |
| Mar 19, 2016 at 16:07 | answer | added | Konstantinos Gaitanas | timeline score: 3 | |
| Mar 19, 2016 at 15:59 | review | Close votes | |||
| Mar 19, 2016 at 16:15 | |||||
| Mar 19, 2016 at 15:52 | comment | added | Fedor Petrov | This has many nice proofs and generalizations. For example, compare the area formula for equilateral triangle with side $a$ $\sqrt{3}/4 a^2$ and the fact that double area must be integer. | |
| Mar 19, 2016 at 15:51 | comment | added | Gerhard Paseman | Nice question. Wrong forum. It might work for math.stackexchange. (Also, it has been proved that equilateral triangles embed in Z^3 and not Z^2.) Gerhard "This Is Not Math.StackExchange Forum" Paseman, 2016.03.19. | |
| Mar 19, 2016 at 15:51 | comment | added | Oai Thanh Đào | I thank to Dr. @LoïcTeyssier for your answer , I am sorry, I edited and post my original question in groups.yahoo.com/neo/groups/AdvancedPlaneGeometry/conversations/… | |
| Mar 19, 2016 at 15:49 | comment | added | Oai Thanh Đào | Thank to Dear Mister @QiaochuYuan , I am sorry, my original equestion in groups.yahoo.com/neo/groups/AdvancedPlaneGeometry/conversations/… | |
| Mar 19, 2016 at 15:44 | history | edited | Oai Thanh Đào | CC BY-SA 3.0 |
Modify the question to ask
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| Mar 19, 2016 at 15:43 | history | undeleted | Oai Thanh Đào | ||
| Mar 19, 2016 at 15:41 | history | deleted | Oai Thanh Đào | via Vote | |
| Mar 19, 2016 at 15:39 | comment | added | Loïc Teyssier | Also the sum of angles must be equal to $\pi$ so of course no all three angles can be rational. | |
| Mar 19, 2016 at 15:38 | comment | added | Qiaochu Yuan | Are you measuring angles in degrees or radians? If degrees, take an equilateral triangle with side lengths $1$. | |
| Mar 19, 2016 at 15:33 | history | asked | Oai Thanh Đào | CC BY-SA 3.0 |