Given a point with trilinear coordinates , the anticevian triangle
of a triangle
with respect to
is a triangle such that
1.
passes through
,
passes through
,
and
passes through
.
2. ,
,
and
pass through
.
3.
is the Cevian triangle of
with respect to
.
The anticevian triangle has trilinear vertex matrix
(1)
|
(Kimberling 1998, pp. 55 and 185), and is a central triangle of type 1 (Kimberling 1998, p. 55).
If
is the Cevian triangle of
and
is an anticevian triangle, then
and
are harmonic conjugates
with respect to
and
.
The following table summarizes a number of special anticevian triangles for various special anticevian points , including their Kimberling center designations.
anticevian point | Kimberling center | anticevian triangle |
incenter | excentral triangle | |
triangle
centroid | anticomplementary triangle | |
symmedian point | tangential triangle |
The side lengths of the anticevian triangle with respect to an anticevian point are given by
(2)
| |||
(3)
| |||
(4)
|
The triangle area of the anticevian triangle for anticevian point with
trilinear coordinates
is
(5)
|
where
is the triangle area of
.