enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Map (mathematics) - Wikipedia

    en.wikipedia.org/wiki/Map_(mathematics)

    A map is a function, as in the association of any of the four colored shapes in X to its color in Y. In mathematics, a map or mapping is a function in its general sense. [1] These terms may have originated as from the process of making a geographical map: mapping the Earth surface to a sheet of paper. [2]

  3. Projection (set theory) - Wikipedia

    en.wikipedia.org/wiki/Projection_(set_theory)

    Projection (mathematics) – Mapping equal to its square under mapping composition; Projection (measure theory) Projection (linear algebra) – Idempotent linear transformation from a vector space to itself; Projection (relational algebra) – Operation that restricts a relation to a specified set of attributes

  4. Presentation of a group - Wikipedia

    en.wikipedia.org/wiki/Presentation_of_a_group

    In mathematics, a presentation is one method of specifying a group.A presentation of a group G comprises a set S of generators—so that every element of the group can be written as a product of powers of some of these generators—and a set R of relations among those generators.

  5. Projection (mathematics) - Wikipedia

    en.wikipedia.org/wiki/Projection_(mathematics)

    A projection may also refer to a mapping which has a right inverse. Both notions are strongly related, as follows. Let p be an idempotent mapping from a set A into itself (thus p ∘ p = p) and B = p(A) be the image of p. If we denote by π the map p viewed as a map from A onto B and by i the injection of B into A (so that p = i ∘ π), then ...

  6. Group theory - Wikipedia

    en.wikipedia.org/wiki/Group_theory

    If X is a set with no additional structure, a symmetry is a bijective map from the set to itself, giving rise to permutation groups. If the object X is a set of points in the plane with its metric structure or any other metric space, a symmetry is a bijection of the set to itself which preserves the distance between each pair of points (an ...

  7. List of set identities and relations - Wikipedia

    en.wikipedia.org/wiki/List_of_set_identities_and...

    This article lists mathematical properties and laws of sets, involving the set-theoretic operations of union, intersection, and complementation and the relations of set equality and set inclusion. It also provides systematic procedures for evaluating expressions, and performing calculations, involving these operations and relations.

  8. Category of sets - Wikipedia

    en.wikipedia.org/wiki/Category_of_sets

    Every set is a projective object in Set (assuming the axiom of choice). The finitely presentable objects in Set are the finite sets. Since every set is a direct limit of its finite subsets, the category Set is a locally finitely presentable category. If C is an arbitrary category, the contravariant functors from C to Set are often an important ...

  9. Axiom schema of replacement - Wikipedia

    en.wikipedia.org/wiki/Axiom_schema_of_replacement

    Indeed, Zermelo set theory (Z) already can interpret second-order arithmetic and much of type theory in finite types, which in turn are sufficient to formalize the bulk of mathematics. Although the axiom schema of replacement is a standard axiom in set theory today, it is often omitted from systems of type theory and foundation systems in topos ...