Cosine Circle
Also called the second Lemoine Circle. Draw lines through the Lemoine Point 
and Parallel to thesides of the Triangles. The points where the antiparallel lines intersect the sides then lie on aCircle known as the cosine circle with center at . The Chords 
, 
, and 
are proportional to the Cosines of the Angles of 
, giving the circleits name.
Triangles 
and are directly similar, andTriangles 
and 
are similar. The Miquel Point of 
is at the Brocard Point 
of .
References
Johnson, R. A. Modern Geometry: An Elementary Treatise on the Geometry of the Triangle and the Circle. Boston, MA: Houghton Mifflin, pp. 271-273, 1929.
- Horned Sphere
- Horner's Method
- Horner's Rule
- Horn Torus
- Horocycle
- Horse Fetter
- Horseshoe Map
- Hough Transform
- Householder's Method
- Howell Design
- H-Spread
- H-Transform
- Hub
- Huffman Coding
- Hull
- Humbert's Theorem
- Hundkurve
- Hundred
- Huntington Equation
- Hunt's Surface
- Hurwitz Equation
- Hurwitz Number
- Hurwitz Polynomial
- Hurwitz-Radon Theorem
- Hurwitz's Irrational Number Theorem