Math 2.0

Group theory and generalizations Definition

Abelian group

Builds on GroupCommutativity

Definition

An abelian group is a group (G,∗)(G, \ast) whose operation is commutative. Thus a∗b=b∗aa \ast b = b \ast a for all a,b∈Ga, b \in G.

Remarks

The integers, the rationals and the real numbers with addition are abelian groups. The operation of an abelian group is often written ++, with identity 00 and inverse −a-a. The group of invertible 2×22 \times 2 real matrices under multiplication is not abelian.

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  1. Binary operation definition
  2. Group concept
  3. Commutativity definition
  4. Abelian group definition

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Further reading

  1. Web https://en.wikipedia.org/wiki/Abelian_group, Definition
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