Difference between revisions of "817 - Algebra"

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# <math>\cdot </math> is distributive over <math> + </math> (on both sides)
 
# <math>\cdot </math> is distributive over <math> + </math> (on both sides)
  
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===Ideals ===
  
 
===Named Rings===
 
===Named Rings===

Revision as of 15:48, 7 December 2022

Groups

Theorems

Topics in Group Theory

Sylow Theory

Semi-Direct Product

Quotient Groups

Isomorphism Theorems

Rings

Definition: A ring is a set \(R\) with two binary operation \( +\) and \(\cdot\) satisfying:

  1. \( (R,+)\) is an abelian group (with identity 0)
  2. \( (R,\cdot) \) is a semigroup
  3. \(\cdot \) is distributive over \( + \) (on both sides)

Ideals

Named Rings

Euclidian Domains (EDs)

A Euclidean Domain (ED) is a domain \(R \) together with a function \(N: R \to \mathbb{Z}_{\geq 0} \) such that \(N(0)=0 \) and the following property holds: for any two elements \( a,b \in R \) with \(b\neq 0 \), there are elements \( q,r \in R\) such that \( a=qb+r \) and either \(r=0 \) or \(N(r)<N(b) \)

Principle Ideal Domains (PIDs)

Unique Factorization Domains (UFDs)