Another Four conics theorem

by daothanhoai, Oct 27, 2014, 2:32 PM

Theorem: Let three conics and one of them touch with fourth conic at two points. Then remaining pair of common tangents intersect at three collinear points.

Special case: Exist a conic touching with three given circles(The conic touching with one circle at two points)
Attachments:
This post has been edited 1 time. Last edited by daothanhoai, Oct 27, 2014, 2:33 PM

Comment

0 Comments

Dao's blog back up: http://oaithanhdao.blogspot.com/

avatar

daothanhoai
Archives
- October 2021
A nice problem associated with refelection
+ April 2015
A generalization of the Simson line theorem
+ March 2015
A generalization Brianchon theorem
+ February 2015
Ten point circle associated X(4240) in ETC
Rectangular circumhyperbola and circle
+ January 2015
A property of a line through circumcenter
A generalization Napoleon theorem associated with the Kiepert
A generalization of Parry circle
A generalization of Nine point circle
Center of six Thebault's circle lie on a conic
Rectangular hyperbola and Inscribed parabola of a triangle
A pair equilateral triangle
+ December 2014
A new inequality in geometry
Seven circles and one conic problem
+ November 2014
Six points lie on a circle associated Botemma configuration
Two conics problem
+ October 2014
Another Four conics theorem
Find Pythagorean number of a triangle
+ September 2014
Cevian triangle associated with Jacobi Configuration
A generalization Simson line theorem
Two similar rectangles theorem
A circle tangent to circumcircle(Similar with the third Fontené)
Concurrency on the Tucker circle
Three lines concurrents
Very nice on three Simson lines
The line through H
+ August 2014
Four centers are cyclic
+ July 2014
A general Zeeman-Gossard theorem-Four Newton lines concurrent
+ June 2014
A Generalization Gossard perspector and X(110)
A conjecture on polynomial function
A line in incircle configuration
A nice generalization Lester theorem
A Theorem on Rectangular hyperbola
Similar Goormaghtigh theorem, with Incenter
A property of incircle X(1)
2nd seven circle theorem
+ May 2014
Two nice line in a triangle
A generalization Newton's line theorem
+ April 2014
Four Centers lie on a circle
Reflection theorem
Three point collinear again
Around reflection of F+,F- in N
A generalization Colling theorem
A generalization of many theorem
X(5463),X(5464)
+ March 2014
Many new circle in a triangle
Two circle, parallel line and collinear 2
Two circle, parallel line and collinear 1
Concurrent again be a point lie on Nine point circle
+ February 2014
Euler line of triangle bounded by three reflection parallel line
A generalization Brianchon's theorem
Eight circles tangent and concurrent at Midpoints of NO
Some problems of seven circles
Jensen's inequality clamp
Pedal circle of a quadrilateral
+ January 2014
A theorem for cyclic quadrilateral
Rhombus in Bicentric
Four incenter lie on a circle in Bicentric quadrilateral
Tangential quadrilateral in quadrilateral(well known??)
Collinear in tangential quadrilateral, and similar tangential...
Homothetic in tangential quadrilateral
No problem
A problem of Thebaul circles
A circle through fixed point
Two Circles, Tangents and Two Collinearities
Property of Mixitilear in circle
Rectangula hypebola
Another four incenter lie on a circles, well known??
Three perpector are collinear
Tangential quadrilateral well known properties?
Focus of Elipse tangent three sidelines at Fa,Fb,Fc
Pascal line formular
Polar-Pole formular
Three circles and a conic
Two concurrent points lie on Pascal line
120 Pascal points lie on circumcircle
Add 6 points into Gacia Capitan's line-9 points are collinear
9 new circles, three new equilaterals and some problem another
Centroid of six equilateral triangle lie on a circle
X3,X16,X110,X2378,X5463 lie on a circle
Fermat point, Incenter, and Equilateral triangles
Pohoata-Dao-Moses circle X5607 and X5608
Six Concyclic Points via Antipedal Triangle
A generalization Napoleon equilateral triangle
Two circles tangent with one circle and Fixed point
A generalization Bottema configuration
A generalization Brahmagupta's configuration
Relative a generalization Bottema theorem
Dao-6 points circle X5569
X15 or X16 and three antipode lie on a circle
A generalization Gibert's circle
A generalization Lester's circle
Tangent of of Kiepert hyperbola at two Kiepert points
D,E,G,X110 lie on a circle
Reflection Fermat points in circumcircle and Nine points circle
Circle through two fixed point lie on Euler line
Two area theorem
Collinear Intersections and Products of Ratios
Two Circles, Tangents and Two Collinearities
A generalization orthotransversal
A line in incircle configuration
Collinear, Harmonic range, and collinear
Viet Nam Hexagon
Pascal's line concurrent
Another seven circle theorem
Fermat point and concurrent point
Maybe Thebault have ovelook
A line transformation
Ceva Conjugate-and six points collinear
A generalization Droz-Farny line 2
A generalization Droz-Farny line 1
Two triangle perpective theorem
Collinear, reflection, and perpective
Shouts
Submit

  • hm i wonder who's 799786

    by heheman, May 12, 2025, 1:16 AM

  • Dead blog lmao

    by 799786, Jun 7, 2022, 11:30 PM

  • Nice Blog! :)

    by Functional_equation, Sep 6, 2020, 4:34 PM

  • Very useful blog :P

    by Kamran011, Apr 26, 2020, 11:26 AM

  • Dataaacvuuv

    by o_i-SNAKE-i_o, Dec 7, 2019, 8:58 AM

  • Wonderful work...so good to see!
    Can I ask you a question on the Simson live/Essay triangle?

    by Notacademic, Jul 13, 2019, 7:41 AM

  • Very Underrated....though amazing blog

    by AlastorMoody, Feb 23, 2019, 4:41 PM

  • Thank to You very much @utkarshgupta :P :P :P :P

    by daothanhoai, Jun 27, 2014, 11:18 AM

  • OK man !! :lol:
    This is some stuff !! :o

    Great Blog :D :D

    by utkarshgupta, Jun 22, 2014, 9:02 AM

  • :maybe: :maybe:

    by daothanhoai, Apr 13, 2014, 3:38 PM

  • I think no one here has a greater interest in Geometry than you have.

    by Ashutoshmaths, Mar 31, 2014, 1:12 PM

  • :maybe: :maybe: :o :P

    by daothanhoai, Feb 11, 2014, 7:06 AM

  • Thank to ThirdTimeLucky.

    by daothanhoai, Feb 11, 2014, 7:06 AM

  • Very nice problems, will surely try them after my exams! :) :oops:

    by ThirdTimeLucky, Feb 10, 2014, 9:02 PM

14 shouts
Tags
About Owner
  • Posts: 406
  • Joined: Sep 18, 2013
Blog Stats
  • Blog created: Oct 6, 2013
  • Total entries: 113
  • Total visits: 47466
  • Total comments: 13
Search Blog
a