Eight Curve
A curve also known as the Gerono Lemniscate. It is given by Cartesian Coordinates
 | (1) |
 | (2) |
 |  |  | (3) |
 | |  | (4) |
The Curvature and Tangential Angle are
 | |  | (5) |
 | |  | (6) |
See also Butterfly Curve, Dumbbell Curve, Eight Surface, Piriform
References
Cundy, H. and Rollett, A. Mathematical Models, 3rd ed. Stradbroke, England: Tarquin Pub., p. 71, 1989. Lawrence, J. D. A Catalog of Special Plane Curves. New York: Dover, pp. 124-126, 1972. Lee, X. ``Lemniscate of Gerono.''http://www.best.com/~xah/SpecialPlaneCurves_dir/LemniscateOfGerono_dir/lemniscateOfGerono.html. MacTutor History of Mathematics Archive. ``Eight Curve.''http://www-groups.dcs.st-and.ac.uk/~history/Curves/Eight.html.
- Quadriplanar Coordinates
- Quadruple
- Quadruple Point
- Quadruplet
- Quadtree
- Quantic
- Quantifier
- Quantization Efficiency
- Quantum Chaos
- Quarter
- Quarter Squares Rule
- Quartet
- Quartic Curve
- Quartic Equation
- Quartic Reciprocity Theorem
- Quartic Surface
- Quartile
- Quartile Deviation
- Quartile Range
- Quartile Skewness Coefficient
- Quartile Variation Coefficient
- Quasiamicable Pair
- Quasiconformal Map
- Quasigroup
- Quasiperfect Number