Castillon's Problem
Inscribe a Triangle in a Circle such that the sides of the Triangle pass through three givenPoints 
, 
, and 
.
References
Dörrie, H. ``Castillon's Problem.'' §29 in 100 Great Problems of Elementary Mathematics: Their History and Solutions. New York: Dover, pp. 144-147, 1965.
- Crossing Number (Link)
- Cross of Lorraine
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- Cross Product
- Cross-Ratio
- Cross-Section
- Crout's Method
- Crowd
- Crown
- Crucial Point
- Cruciform
- Crunode
- Cryptarithm
- Cryptarithmetic
- Cryptography
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- Csch
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- C-Table
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- Cube 2-Compound
- Cube 3-Compound
- Cube 4-Compound
- Cube 5-Compound
- Cubed