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) = a[a3(b + c)2 + a(ab + ac - 2bc)(b2 + c2) - bc(b3 + c3) - a(b4 + c4) - (b5 + c5)]
= g(a,b,c) : g(b,c,a) : g(c,a,b), where g(a,b,c) = (r2 - s2) cos A + 2rs sin A
Barycentrics af(a,b,c) : bf(b,c,a) : cf(c,a,b)
The Apollonius circle is described at X(182) as the circle tangent to the three excircles and encompassing them. That X(970) is its center was noted on New Year's Day, 2002, by Paul Yiu. (Hyacinthos #4619-4623)
X(970) lies on these lines: 1,181 3,6 5,10 21,51 40,43 185,411