Search results
Results from the WOW.Com Content Network
In mathematics, an unordered pair or pair set is a set of the form {a, b}, i.e. a set having two elements a and b with no particular relation between them, where {a, b} = {b, a}. In contrast, an ordered pair ( a , b ) has a as its first element and b as its second element, which means ( a , b ) ≠ ( b , a ).
In this setting, an edge is an unordered pair of vertices, and a two-edge graph is an unordered pair of edges. The number of possible edges is a triangular number, and the number of pairs of edges (allowing both edges to connect the same two vertices) is a doubly triangular number. [4]
Mathematics. 2 (number), two of something, a pair; Unordered pair, or pair set, in mathematics and set theory; Ordered pair, or 2-tuple, in mathematics and set theory; Pairing, in mathematics, an R-bilinear map of modules, where R is the underlying ring; Pair type, in programming languages and type theory, a product type with two component types
Lattices, partial orders in which each pair of elements has a greatest lower bound and a least upper bound. Many different types of lattice have been studied; see map of lattices for a list. Partially ordered sets (or posets ), orderings in which some pairs are comparable and others might not be
Theorem: If A and B are sets, then there is a set A×B which consists of all ordered pairs (a, b) of elements a of A and b of B. Proof: The singleton set with member a, written {a}, is the same as the unordered pair {a, a}, by the axiom of extensionality. The singleton, the set {a, b}, and then also the ordered pair
Each cell of the array is either empty or contains an unordered pair from the set of symbols; Each symbol occurs exactly once in each row and column of the array; Every unordered pair of symbols occurs in exactly one cell of the array. An example, a Room square of order seven, if the set of symbols is integers from 0 to 7:
In NFU, all the set definitions given work by stratified comprehension; in ZFC, the existence of the unordered pair is given by the Axiom of Pairing, the existence of the empty set follows by Separation from the existence of any set, and the binary union of two sets exists by the axioms of Pairing and Union (= {,}).
The first book on the systematic algebraic solutions of linear and quadratic equations by the Persian scholar Muhammad ibn Mūsā al-Khwārizmī. The book is considered to be the foundation of modern algebra and Islamic mathematics. [10] The word "algebra" itself is derived from the al-Jabr in the title of the book. [11]