Fuhrmann Triangle
The Fuhrmann triangle of a Triangle 
is the Triangle 
formed by reflecting theMid-Arc Points 
, 
, 
about the lines 
, 
, and 
. TheCircumcircle of the Fuhrmann triangle is called the Fuhrmann Circle, and the lines 
, 
, and
Concur at the Circumcenter 
.
References
Fuhrmann, W. Synthetische Beweise Planimetrischer Sätze. Berlin, p. 107, 1890. Johnson, R. A. Modern Geometry: An Elementary Treatise on the Geometry of the Triangle and the Circle. Boston, MA: Houghton Mifflin, pp. 228-229, 1929.
- Closed Interval
- Closed Set
- Close Packing
- Closure
- Clothoid
- Clove Hitch
- Clump
- Cluster
- Cluster Perimeter
- C-Matrix
- Coanalytic Set
- Coastline Paradox
- Coates-Wiles Theorem
- Coaxal Circles
- Coaxaloid System
- Coaxal System
- Cobordant Manifold
- Cobordism
- Cobordism Group
- Cobordism Ring
- Cochleoid
- Cochleoid Inverse Curve
- Cochloid
- Cochran's Theorem
- Cocked Hat Curve