Tusi Couple

Tusi couple

The Tusi couple is a 2-cusped hypocycloid obtained by rolling a circle of radius a inside a circle of radius 2a. The result is a line segment (Steinhaus 1999, p. 145; Kanas 2003), as noted by the Persian astronomer and mathematician Nasir Al-Din al-Tusi (1201-1274) (Sotiroudis and Paschos 1999, p. 60; Kanas 2003).

See also


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Kanas, N. "From Ptolemy to the Renaissance: How Classical Astronomy Survived the Dark Ages." Sky & Telescope 105, 50-58, Jan. 2003.Sotiroudis, P. and Paschos, E. A. The Schemata of the Stars: Byzantine Astronomy from A.D. 1300. Singapore: World Scientific, 1999.Steinhaus, H. Mathematical Snapshots, 3rd ed. New York: Dover, 1999.

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Tusi Couple

Cite this as:

Weisstein, Eric W. "Tusi Couple." From MathWorld--A Wolfram Web Resource.

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