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Hyacinthos · We discuss themes on Triangle Geometry

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  • Members: 391
  • Category: Geometry
  • Founded: Dec 22, 1999
  • Language: English
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Messages 20996 - 21025 of 21025   Oldest  |  < Older  |  Newer >  |  Newest
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20996 Barry Wolk
wolkbarry Offline Send Email
Apr 30, 2012
10:08 pm
I have a strange result. Let P be any point on the conic through ABCHI. Then the cevian circle of P goes through the Feuerbach point.   Generalizations? -- ...
20997 Randy Hutson
rhutson2 Online Now Send Email
Apr 30, 2012
11:51 pm
One generalization: Let P be any point on the rectangular hyperbola ABCHQ. Then the cevian circle of P goes through the center of the hyperbola (on the...
20998 Alexey Zaslavsky
zasl@... Send Email
May 2, 2012
5:48 am
Dear Randy and Barry! Yes this is well known. The synthetic proof is in our with Akopjan book "Geometry of conics". Sincerely...
20999 forumgeom forumgeom
ForumGeom@... Send Email
May 2, 2012
12:58 pm
The following paper has been published in Forum Geometricorum. It can be viewed at http://forumgeom.fau.edu/FG2012volume12/FG201212index.html The editors Forum...
21000 Chandan Banerjee
cbanerjee.2011 Offline Send Email
May 7, 2012
8:45 am
I have posted a synthetic proof of this problem here:- http://www.artofproblemsolving.com/blog/69529...
21001 Randy Hutson
rhutson2 Online Now Send Email
May 7, 2012
9:59 pm
Chandan, I haven't looked at the whole proof yet, but one correction I note: replace 'vertex of the hyperbola' with 'center of the hyperbola'. Best regards, ...
21002 Jean-Louis Ayme
jeanlouisayme Offline Send Email
May 8, 2012
8:17 am
Dear Hyacinthists, an article in English concerning “Two parallel tangent theorems’’ has been put on my website with a lot of new proofs. ...
21003 fqces Offline Send Email May 8, 2012
8:46 am
Dear friends, Some years ago Paul Yiu posted at Hyacinthos several results about two interesting points, namely the intersections of the De Longchamps line...
21004 Francisco Javier
garciacapitan Offline Send Email
May 8, 2012
10:19 am
I did a search and they weren't found....
21005 Antreas Hatzipolakis
xpolakis Offline Send Email
May 8, 2012
10:39 am
Are these triangle **centers** in order to be included in ETC? APH ... [Non-text portions of this message have been removed]...
21006 Francisco Javier
garciacapitan Offline Send Email
May 8, 2012
10:51 am
They are, that is, a cyclic permutation of one of the points gives the same point....
21007 Bernard Gibert
bernardgibert Offline Send Email
May 8, 2012
10:58 am
Dear Quim ... these points are real only when ABC is obtuseangle so I expect this is the end of the story... Best regards Bernard [Non-text portions of this...
21008 Jean-Louis Ayme
jeanlouisayme Offline Send Email
May 8, 2012
12:24 pm
Dear Hyacinthists,   My conjecture   1. ABC a triangle, 2. P a point 3. (1a) the circumcircle of the triangle PBC and circularly 4. A’ the second point of...
21009 Randy Hutson
rhutson2 Online Now Send Email
May 8, 2012
1:45 pm
There are other centers in ETC that are real only for certain triangles, for exampleX(5000) = WALSMITH POINT, which is complex when ABC is obtuse, and the...
21010 Jean-Louis Ayme
jeanlouisayme Offline Send Email
May 8, 2012
1:51 pm
Dear Mathlinkers, I correct the typo of the note   1. ABC a triangle, 2. P a point 3. (1a) the circumcircle of the triangle PBC and circularly 4. A’ the...
21011 Chandan Banerjee
cbanerjee.2011 Offline Send Email
May 8, 2012
1:52 pm
So it seems that the two points which are being discussed in this post are anti-complements of the 1st and 2nd Grinberg Intersections. ... -- CHANDAN [Non-text...
21012 Chandan Banerjee
cbanerjee.2011 Offline Send Email
May 8, 2012
2:02 pm
I have posted a solution to this problem here:- http://www.artofproblemsolving.com/Forum/viewtopic.php?f=46&t=478701...
21013 Francisco Javier
garciacapitan Offline Send Email
May 8, 2012
7:47 pm
A (non-symmetric) coordinates are {2 a^2 b^2 c^2, -c^2(a^4 + b^4 - c^4 + R), b^2(-a^4+b^4-c^4 + R )}, {2 a^2 b^2 c^2, c^2 (-a^4 - b^4 + c^4 + R), -b^2...
21014 forumgeom forumgeom
ForumGeom@... Send Email
May 9, 2012
9:34 pm
The following paper has been published in Forum Geometricorum. It can be viewed at http://forumgeom.fau.edu/FG2012volume12/FG201213index.html The editors Forum...
21015 CESAR
cesar_e_lozada Offline Send Email
May 9, 2012
9:48 pm
Barycentrics: u = f(SA, SB, SC) and f(SA, SB, SC) = 1/((SB+SC)*((SB+SC)*(SA^2-SB*SC)+(SB-SC)*(SA*(SB-SC)+`&+-`(2*sqrt(-SA*SB*SC*(SA+SB+SC)))))) There is + -...
21016 nguyenle2005usa Offline Send Email May 11, 2012
6:40 am
Dear friends, Theorem 28 of Norman Wildberger's paper, "Universal Hyperbolic Geometry III: First steps in Projective Triangle Geometry" which has recently...
21017 Angel
amontes1949 Offline Send Email
May 15, 2012
7:14 pm
Dear Hyacinthists, Given a triangle ABC, let I be the incenter, let F be Feuerbach point, and let t be the tangent in F to the incircle. The perpendiculars...
21018 Ricardo Barroso
ricardobca Offline Send Email
May 15, 2012
8:08 pm
Dear Hyacinthists In http://personal.us.es/rbarroso/trianguloscabri/ two probelms.. a locus of Trigueros R. and    Alhazen problem Best regards Ricardo ...
21019 César Lozada
cesar_e_lozada Offline Send Email
May 17, 2012
6:57 pm
Dear Geometers: Doing a pure mathematical-programming exercise, I tried to find triangle centers on circles concentric with circumcircle, i.e., circles passing...
21020 Barry Wolk
wolkbarry Offline Send Email
May 22, 2012
8:09 pm
From: Angel amontes1949@... ... Here is a generalization. Given three lines L1, L2, L3 that meet at P=(p1,p2,p3), find all lines L such that, if L meets...
21021 Alexey Zaslavsky
zasl@... Send Email
May 23, 2012
11:06 am
Dear colleagues! Let a triangle ABC be given. Consider two extremal problems. (1) Find a point X_p minimizing the sum X_pA^p+X_pB^p+X_pC^p (2) Find a points...
21022 Chandan Banerjee
cbanerjee.2011 Offline Send Email
May 24, 2012
12:25 pm
Given a circle and a point P inside it, cut the circle into 8 pieces using chords through P such that the angle between any two consecutive chords is 45...
21023 Francisco Bellot
p28121941 Offline Send Email
May 24, 2012
1:10 pm
This is the so called pizza theorem, and it is in fact well known. I suggest search first in the net before posting, say with absolute respect to the opinions...
21024 Chandan Banerjee
cbanerjee.2011 Offline Send Email
May 24, 2012
2:44 pm
Thank you for your opinion. I am extremely sorry if I offended you or anyone else. I didn't mean any disrespect....
21025 Chris Van Tienhoven
chris.vantie... Offline Send Email
7:20 am
... Dear Francisco, I am glad with every contribution or question. Known or unknown, brilliant or diffuse, thought-out or preliminary, researched or not. Ain't...
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