The Area of the Excentral Triangle

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Let be the area of the triangle formed by the excenters of a triangle with perimeter
and circumradius
. Then
.
Contributed by: Jay Warendorff (March 2011)
Open content licensed under CC BY-NC-SA
Snapshots
Details
See Theorem 233 in N. Altshiller-Court, College Geometry: An Introduction to the Modern Geometry of the Triangle and the Circle, Mineola, NY: Dover, 2007 p. 113.
Permanent Citation
"The Area of the Excentral Triangle"
http://demonstrations.wolfram.com/TheAreaOfTheExcentralTriangle/
Wolfram Demonstrations Project
Published: March 7 2011