X2963¶
BARYCENTRIC PRODUCT X17*X18
X2963 (BARYCENTRIC PRODUCT X17*X18) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶
Constructed Elements
Related Centers: X590 (ISOGONAL CONJUGATE OF X588), X615 (ISOGONAL CONJUGATE OF X589)
Alternate Coordinates1 form
Barycentrics: \(1/(a^{4} + b^{4} + c^{4} - 2 a^{2} b^{2} - 2 a^{2} c^{2} - b^{2} c^{2}) : :\)
Functional Relations11 relations
X2963 = isogonal conjugate of X1994
X2963 = X570-cross conjugate of X6
X2963 = crosssum of Xi and Xj for these (i,j): (6, 195), (49, 2965)
X2963 = isotomic conjugate of X7769
X2963 = X2-isoconjugate of X2964
X2963 = polar conjugate of X32002
X2963 = perspector of ABC and unary cofactor triangle of Kosnita triangle
X2963 = barycentric product of nine-point centers of 1st and 2nd Ehrmann inscribed triangles
Notes¶
Let Q be the pedal curve (a limaçon of Pascal) of the circle with center X7728 and radius |OH|, with respect to X265. Let A'B'C' be the triangle formed by the tangents at A, B, C to Q. Then the triangles ABC and A'B'C' are perspective, and their perspector is X2963. Moreover, X21975 is the only finite fixed point of the affine transformation that maps a triangle ABC onto A'B'C'. See X21975 (X(21975).png). (Angel Montesdeoca, September 10, 2019)
In the plane of a triangle ABC, let
N= Nine point circle,
N'a, A' = reflection of N, A in BC, define N'b, B' and N'c, C' cyclically
Pa = polar of A' with respect to N'a, and define Pb and Pc cyclically;
A″ = Pc∩Pb, and define B″ and C″ cyclically.
The triangle A″B″C″ is perspective to ABC, and the perspector is X2963. (Dasari Naga Vijay Krishna, June 8, 2021)
Generalization of Vijay’s construction of X2963. Let C(U) = the circle with powers u, v, w with respect to the vertices A, B, C, respectively;
C'(U) = reflection of C(U) in side BC;
A' = reflection of A in in side BC;
Pa = polar of A in C'(U), and define Pb and Pc cyclically;
A″ = Pc∩Pb, and define B″ and C″ cyclically.
The triangle A″B″C″ is perspective to ABC, and the perspector is
a^2 / (a^2*(a^2*b^2 - b^4 + a^2*c^2 + b^2*c^2 - c^4) + a^2*(b^2 + c^2 - u)*u - (a^4 + a^2*b^2 - b^4 + 2*b^2*c^2 - c^4)*v + (a^2 + b^2 - c^2)*v^2 - (a^4 - b^4 + a^2*c^2 + 2*b^2*c^2 - c^4)*w + (a^2 - b^2 + c^2)*w^2 - a^2*(u*v + u*w - v*w)) : : (Peter Moses, June 11, 2021)