Klein's Equation
If a Real curve has no singularities except nodes and Cusps, Bitangents, and Inflection Points, then
where
is the order, 
is the number of conjugate tangents, 
is the number of Realinflections, 
is the class, 
is the number of Real conjugate points, and 
is thenumber of Real Cusps. This is also called Klein's Theorem.See also Plücker's Equation
References
Coolidge, J. L. A Treatise on Algebraic Plane Curves. New York: Dover, p. 114, 1959.
- Archimedes Algorithm
- Archimedes' Axiom
- Archimedes' Cattle Problem
- Archimedes' Circles
- Archimedes' Constant
- Archimedes' Hat-Box Theorem
- Archimedes' Lemma
- Archimedes' Midpoint Theorem
- Archimedes' Postulate
- Archimedes' Problem
- Archimedes' Recurrence Formula
- Archimedes' Spiral
- Archimedes' Spiral Inverse
- Arc Length
- Arc Minute
- Arcsecant
- Arc Second
- Arcsine
- Arctangent
- Area
- Area Element
- Areal Coordinates
- Area-Preserving Map
- Area Principle
- Arf Invariant