In mathematics, Poinsot's spirals are two spirals represented by the polar equations
where csch is the hyperbolic cosecant, and sech is the hyperbolic secant.[1] They are named after the French mathematician Louis Poinsot.
Examples of the two types of Poinsot's spirals
 The Poinsot spiral r=csch(θ/3). |
 The Poinsot spiral r=sech(θ/3). |
See also
- Cotes's spiral – Plane curve
References
- ^ Lawrence, J. Dennis (1972). A Catalog of Special Plane Curves. New York: Dover. pp. 192–194. ISBN 0486602885.
| Curves |  | ||
|---|---|---|---|
| Helices |
| ||
| Spirals | |||