Orthogonal Vectors
Two vectors 
and 
whose Dot Product is 
(i.e., the vectors arePerpendicular) are said to be orthogonal. In 3-space, three vectors can be mutually perpendicular.
- Upper Bound
- Upper Integral
- Upper Limit
- Upper Sum
- Upper-Trimmed Subsequence
- Upward Drawing
- Urchin
- Utility Graph
- Utility Problem
- Valence
- Valency
- Valuation
- Valuation Group
- Valuation Ring
- Valuation Theory
- Value
- Value (Game)
- Vampire Number
- van der Grinten Projection
- Vandermonde Determinant
- Vandermonde Identity
- Vandermonde Matrix
- Vandermonde's Sum
- Vandermonde Theorem
- van der Pol Equation