X113

JERABEK ANTIPODE

< A B C >: Reference Triangle △ABC [ A B ]: Sideline AB (Base c = 1) [ B C ]: Sideline BC (Side a) [ C A ]: Sideline CA (Side b) circumcircle: Circumcircle of △ABC { 6, 13 }: Central Line L(6, 13) { 2, 74 }: Central Line L(2, 74) { 4, 110 }: Central Line L(4, 110) { 3, 122 }: Central Line L(3, 122) A = Vertex A (0.0000, 0.0000) B = Vertex B (1.0000, 0.0000) C = Vertex C (0.6122, 0.5999) X_3 = CIRCUMCENTER (0.5000, 0.1021) X_6 = SYMMEDIAN POINT (LEMOINE POINT, GREBE POINT) (0.6000, 0.2672) X_13 = 1st ISOGONIC CENTER (FERMAT POINT, TORRICELLI POINT) (0.5879, 0.2819) X_2 = CENTROID (0.5374, 0.2000) X_74 = ISOGONAL CONJUGATE OF EULER INFINITY POINT (0.7484, -0.3437) X_4 = ORTHOCENTER (0.6122, 0.3958) X_110 = FOCUS OF KIEPERT PARABOLA (0.2516, 0.5478) X_122 = -OF-MEDIAL-TRIANGLE (0.5195, -0.0036) X_113 = JERABEK ANTIPODE (0.4319, 0.4718) A B C X3 X6 X13 X2 X74 X4 X110 X122 X113 (a, b, c) = (5, 6, 7) | AB = 1

X113 (JERABEK ANTIPODE) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).

Constructed Elements

  • Circle: Circumcircle (circumcircle) — Passes through vertices A, B, C; centered at X3 CIRCUMCENTER

  • Related Centers: X3 (CIRCUMCENTER)

Trilinears: \(\sin B \sin C [(\sin C)/(\cos C - 2 \cos A \cos B) + (\sin B)/(\cos B - 2 \cos A \cos C)] : :\)
Barycentrics: \((\sin C)/(\cos C - 2 \cos A \cos B) + (\sin B)/(\cos B - 2 \cos A \cos C) : :\)
Search Value (6, 9, 13): \(-2.384528218412\)
▸ Alternate Coordinates2 forms
  • Barycentrics: \(b^{2}\)/(\(b^{2}\)\(S_{B}\) - \(2S_{A}\)\(S_{C})\) + \(c^{2}\)/(\(c^{2}\)\(S_{C}\) - \(2S_{A}\)\(S_{B})\) : : (Peter J. C. Moses, 3/2003)

  • Barycentrics: \((2a^{4} - b^{4} - c^{4} - a^{2}b^{2} - a^{2}c^{2} + 2b^{2}c^{2})[a^{4}(b^{2} + c^{2}) - 2a^{2}(b^{4} - b^{2}c^{2} + c^{4}) + (b^{2} - c^{2})^{2}(b^{2} + c^{2})] : :\)

X113 lies on the bicevian conic of X2 and X110, the Walsmith rectangular hyperbola.

▸ Incident Central Lines11 lines

{2, 74}, {3, 122}, {4, 110}, {5, 125}, {6, 13}, {11, 942}, {52, 135}, {114, 690}, {123, 960}, {127, 141}, {137, 546}

▸ Functional Relations29 relations

Notes

Let HaHbHc be the orthic triangle. Let L be the line through Ha parallel to the Euler line, and define M and N cyclically. Let L' be the reflection of L in sideline BC, and define M' and N' cyclically. The lines L', M', N' concur in X113. (Randy Hutson, August 26, 2014)

Let HaHbHc be the orthic triangle. Let MA be the reflection of the orthic axis in line HbHc, and define Let MB and Let MC cyclically. Let A″ = Let MB∩MC, and define B″ and C″ cyclically. The lines HaA″, HbB″ HcC″ concur in X113. (Randy Hutson, August 26, 2014)

Let HaHbHc be the orthic triangle. Let NA be the orthic axis of AHbHc, and define NB and NC cyclically. Let A″ = NB∩NC, B″ = NC∩AC, C″ = NA∩BC. Then triangle A″B″C″ is inversely similar to ABC, with similitude center X6, and the lines HaA″, HbB″, HcC″ concur in X113. Also, X113 = X3-of-A″B″C″. (Randy Hutson, August 26, 2014)