Delta Curve

A curve which can be turned continuously inside an equilateral triangle. There are an infinite number of delta curves, but the simplest are the circle and lens-shaped Delta-biangle. All the Delta curves of height h have the same perimeter 2pih/3. Also, at each position of a Delta curve turning in an equilateral triangle, the perpendiculars to the sides at the points of contact are concurrent at the instantaneous center of rotation.

See also

Equilateral Triangle, Lens, Reuleaux Polygon, Reuleaux Triangle, Rotor

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Honsberger, R. Mathematical Gems I. Washington, DC: Math. Assoc. Amer., pp. 56-59, 1973.

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Delta Curve

Cite this as:

Weisstein, Eric W. "Delta Curve." From MathWorld--A Wolfram Web Resource.

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