irrational set
1Irrational number — In mathematics, an irrational number is any real number that is not a rational number that is, it is a number which cannot be expressed as a fraction m / n , where m and n are integers, with n non zero. Informally, this means numbers that cannot… …
2Irrational rotation — In mathematics, an irrational rotation is a map:r : [0,1] ightarrow [0,1] given by: r(x) = x + heta mod 1 (see modular arithmetics) where θ is an irrational number. The name comes from the fact that this map comes from a rotation by an angle of θ …
3Set (mathematics) — This article gives an introduction to what mathematicians call intuitive or naive set theory; for a more detailed account see Naive set theory. For a rigorous modern axiomatic treatment of sets, see Set theory. The intersection of two sets is… …
4irrational number — noun Date: 1551 a number that can be expressed as an infinite decimal with no set of consecutive digits repeating itself indefinitely and that cannot be expressed as the quotient of two integers …
5Cantor set — In mathematics, the Cantor set, introduced by German mathematician Georg Cantor in 1883 [Georg Cantor (1883) Über unendliche, lineare Punktmannigfaltigkeiten V [On infinite, linear point manifolds (sets)] , Mathematische Annalen , vol. 21, pages… …
6Gδ set — In the mathematical field of topology, a Gδ set, is a subset of a topological space that is a countable intersection of open sets. The notation originated in Germany with G for ( German : area) meaning open set in this case and δ for ( German :… …
7Borel set — In mathematics, a Borel set is any set in a topological space that can be formed from open sets (or, equivalently, from closed sets) through the operations of countable union, countable intersection, and relative complement. Borel sets are named… …
8Proof that π is irrational — Although the mathematical constant known as pi; (pi) has been studied since ancient times, and so has the concept of irrational number, it was not until the 18th century that π was proved to be irrational.In the 20th century, proofs were found… …
9Non-Borel set — In mathematics, a non Borel set is a set that cannot be obtained from simple sets by taking complements and at most countable unions and intersections. (For the definition see Borel set.) Only sets of real numbers are considered in this article.… …
10Predictably Irrational — Infobox Book name = Predictably Irrational: The Hidden Forces That Shape Our Decisions title orig = translator = image caption = author = Dan Ariely illustrator = cover artist = country = USA language = English series = subject = genre =… …
