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Relations, functions and equivalence

Relations as sets of pairs; reflexive, symmetric, transitive; functions and bijections.

A relation is a set of ordered pairs; an equivalence relation (reflexive, symmetric, transitive) partitions its set into classes; a function is a relation with exactly one output per input. Picture it: "same remainder mod 3" splits the integers into three columns. Think it: a bijection is how we say two sets have the same size, including infinite ones.

Eżempju maħdum · truth table of p implies q

Discrete-Math · Propositional-Logic

Truth table of p implies q

Pass b'pass

  1. p \Rightarrow q

    2 variable(s) → 4 rows. Fill in every combination.

  2. \

    Contingent: true for some inputs, false for others.

Jiżvelaw it-tweġiba
p \Rightarrow q

Issa inti Agħżel problema, jew ittajpja jew iġbed tiegħek stess.Kull pass, stampa, it-tweġiba moħbija sakemm inti tistaqsi.

Żomm tiegħek stess li jaħdmu

Kont b'xejn iżid noti fuq kull lezzjoni, rekord ta' dak li lest, problemi solvuti tiegħek f'post wieħed, u għalliem inti tista' tistaqsi dwar din il-paġna.Il-matematika nnifisha hija miftuħa għal kulħadd, log fil jew le.

Irreġistra issa Login

Simboli użati hawnhekk

Taptap kwalunkwe simbolu għad-definizzjoni sħiħa, stampa, u dak li kull ittra fiha tfisser.

Kif għandek tuża: Relations, functions and equivalence

  1. 2 variable(s) → 4 rows. Fill in every combination.
  2. Contingent: true for some inputs, false for others.

Mistoqsijiet li n-nies jistaqsu

Are some infinities bigger than others?

Yes. The integers and the rationals can be listed; the real numbers cannot (Cantor's diagonal argument), so there are strictly more reals than integers.

What is the difference between a relation and a function?

A relation pairs inputs with outputs freely; a function is a relation in which every input gets exactly one output.

Aktar fil Set Theory & Logic

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