The Fuhrmann Circle

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Let ABC be a triangle. Let A', B', and C' be the midpoints of the arcs BC, AC, and AB on the circumcircle. Let A'', B'', and C'' be the reflections of A', B', and C' across the sides of the triangle. Then A'', B'', C'', the orthocenter H, and the Nagel point N all lie on a circle (called the Fuhrmann circle).

External Links

Circumcircle (Wolfram MathWorld)
Concyclic (Wolfram MathWorld)
Fuhrmann Circle (Wolfram MathWorld)
Nagel Point (Wolfram MathWorld)
Orthocenter (Wolfram MathWorld)
Reflection (Wolfram MathWorld)

Permanent Citation

Jay Warendorff
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​"The Fuhrmann Circle"​
​http://demonstrations.wolfram.com/TheFuhrmannCircle/​
​Wolfram Demonstrations Project​
​Published: March 10, 2011