Interactive Applet |
You can move the points A, B and C (click on the point and drag it).
Press the keys “+” and “−” to zoom in or zoom out the visualization window and use the arrow keys to translate it.
You can also construct all centers related with this one (as described in ETC) using the “Run Macro Tool”. To do this, click on the icon , select the center name from the list and, then, click on the vertices A, B and C successively.
Information from Kimberling's Encyclopedia of Triangle Centers |
Trilinears f(a,b,c) : f(b,c,a) : f(c,a,b),
where f(a,b,c) = bc(b2-c2)[2(a2-b2)(c2-a2) + 3R2(2a2-b2-c2) - a2(a2+b2+c2) + a4+b4+c4],
where R = (a csc A)/2 = circumradius of ABC.Barycentrics af(a,b,c) : bf(b,c,a): cf(c,a,b)
The Lester circle passes through the points X(3), X(5), X(13), X(14). Coordinates of the center were determined by Milorad Stevanovic (#5895, 9/20/02). The circle is described in
June Lester, "Triangles III: complex centre functions and Ceva's theorem," Aequationes Mathematicae 53 (1997) 4-35.
X(1116) lies on these lines: 115,125 140,523