# ordered pair meaning

EN
WOrdered pair
• In mathematics, an ordered pair (a, b) is a pair of mathematical objects. The order in which the objects appear in the pair is significant: the ordered pair (a, b) is different from the ordered pair (b, a) unless a = b.
• Ordered pairs are also called 2-tuples, or sequences of length 2; ordered pairs of scalars are also called 2-dimensional vectors.
• 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 second coordinates, or the left and right projections of the ordered pair.

## Definition of ordered pair in English Dictionary

• Noun
1. (set theory) An object containing exactly two elements in a fixed order, so that, when the elements are different, exchanging them gives a different object. Notation: (a, b) or.
1. If an ordered pair were defined (in terms of sets) as then the "first element" of an ordered pair S could be defined as CAR(S) where CAR(S) = x if and only if . Likewise, the "second element" of S could be defined as CDR(S) where CDR(S) = x if and only if . If the two elements happened to be equal, then the ordered pair would still have cardinality two as would be naturally expected.
• Part-of-Speech Hierarchy
1. Nouns
• Countable nouns 0 0 Grammatically, this idiom "ordered pair" is a noun, more specifically, a countable noun.