Math 2.0

example

The integers modulo the even integers

Example

Let G=(Z,+)G = (\mathbb{Z}, +) be the integers with addition, and let N=2ZN = 2\mathbb{Z} be the even integers. NN is normal, because GG is abelian. NN has two cosets: NN, the even integers, and 1+N1 + N, the odd integers. The sum of two odd integers is even, so (1+N)+(1+N)=N(1 + N) + (1 + N) = N. Thus the quotient group Z/2Z\mathbb{Z}/2\mathbb{Z} has two elements, with identity NN. It is the integers modulo 22.

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  1. Group concept
  2. Integers object
  3. Integers modulo n concept
  4. Conjugate elements definition
  5. Subgroup definition
  6. Conjugate subgroup definition
  7. Left coset definition
  8. Right coset definition
  9. Normal subgroup definition
  10. Normality via left and right cosets statement
  11. Quotient group definition
  12. The integers modulo the even integers example

Sources

  1. Web https://en.wikipedia.org/wiki/Quotient_group, Even and odd integers