- ordered pair
- An object associated with a set of two objects considered in a particular order. Thus the ordered pair <a,b> is not identical with the ordered pair <b,a>, just as the queue ‘a first and b next’ is not the queue ‘b first and a next’. In set theory, ordered pairs cannot be identified with the set of their members, since a,b = b,a, which is exactly what we do not want. The task is to find sets with the property that <a,b> ? <b,a> if a ? b, and with the property that if <a,b> = <u,v> then a = u and b = v. One solution is that of Kazimierz Kuratowski (b. 1896), that identifies the ordered pair <a,b> with the set a,a,b. This is the definition in general use today. See also Cartesian product.

*Philosophy dictionary.
Academic.
2011.*

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**Ordered pair**— In mathematics, an ordered pair (a, b) is a pair of mathematical objects. In the ordered pair (a, b), the object a is called the first entry, and the object b the second entry of the pair. Alternatively, the objects are called the first and… … Wikipedia**ordered pair**— Math. two quantities written in such a way as to indicate that one quantity precedes or is to be considered before the other, as (3, 4) indicates the Cartesian coordinates of a point in the plane. [1950 55] * * * … Universalium**ordered pair**— noun A set containing exactly two elements in a fixed order, so that, when the elements are different, exchanging them gives a different set. Notation: (a, b) or See Also: triple, triplet, tuple … Wiktionary**ordered pair**— Math. two quantities written in such a way as to indicate that one quantity precedes or is to be considered before the other, as (3, 4) indicates the Cartesian coordinates of a point in the plane. [1950 55] … Useful english dictionary**ordered pairs**— ordered pair … Philosophy dictionary**ordered**— adj. 1. having or evincing a systematic arrangement; especially, having elements succeeding in order according to rule; as, an ordered sequence; an ordered pair. Opposite of {disordered} or {unordered}. [Narrower terms: {abecedarian,… … The Collaborative International Dictionary of English**ordered n-tuple**— A generalization of the notion of an ordered pair to sequences of n objects. The ordered n tuple < x 1… x n > can be treated as < < x 1… x n–1 >, x n >, i.e. the ordered pair that has the first n – 1 objects as first member, and … Philosophy dictionary**Pair**— The word pair, derived via the French words pair/paire from the Latin par equal , can refer to:* 2 (number), two of something * Topological pair, an inclusion of topological spaces. * Au pair, a work agreement * Couple, various senses for two… … Wikipedia**Pair of spaces**— In mathematics, particularly algebraic topology, a pair of spaces is an ordered pair ( X , A ) where X is a topological space and A a subspace (with the subspace topology). The use of pairs of spaces is sometimes more convenient and technically… … Wikipedia**Ordered vector space**— A point x in R2 and the set of all y such that x≤y (in red). The order here is x≤y if and only if x1 ≤ y1 and x2 ≤ y2. In mathematics an ordered vector space or partially ordered vector space is a vector space equi … Wikipedia