Spijker's Lemma
The image on the Riemann Sphere of any Circle under a Complex rational mapping withNumerator and Denominator having degrees no more than 
has length no longer than 
.
References
Edelman, A. and Kostlan, E. ``How Many Zeros of a Random Polynomial are Real?'' Bull. Amer. Math. Soc. 32, 1-37, 1995.
- Brown's Criterion
- Broyden's Method
- Bruck-Ryser-Chowla Theorem
- Bruck-Ryser Theorem
- Brunnian Link
- Brunn-Minkowski Inequality
- Brun's Constant
- Brun's Sum
- Brun's Theorem
- Brute Force Factorization
- B-Spline
- B-Tree
- Bubble
- Buchberger's Algorithm
- Buckminster Fuller Dome
- Buffon-Laplace Needle Problem
- Buffon's Needle Problem
- Bulirsch-Stoer Algorithm
- Bullet Nose
- Bumping Algorithm
- Bundle
- Burau Representation
- Burkhardt Quartic
- Burnside Problem
- Burnside's Conjecture