Show that ##G\simeq \mathbb{Z}/2p\mathbb{Z}##

  • Thread starter Thread starter JojoF
  • Start date Start date
  • Tags Tags
    Group theory
Click For Summary
SUMMARY

The discussion centers on proving that a group \( G \) of order \( 2p \) (where \( p \) is an odd prime) is isomorphic to \( \mathbb{Z}/2p\mathbb{Z} \) under the assumption that \( G \) is abelian. The key insight is that \( G \) must be cyclic, as any two cyclic groups of the same order are isomorphic. The relevance of the Sylow theorems, particularly the first Sylow theorem, is emphasized, as all subgroups in an abelian group are normal, which simplifies the proof process.

PREREQUISITES
  • Understanding of group theory, specifically the properties of abelian groups.
  • Familiarity with Sylow theorems and their implications in group structure.
  • Knowledge of cyclic groups and their characteristics.
  • Basic concepts of isomorphism in the context of group theory.
NEXT STEPS
  • Study the first Sylow theorem and its application in group theory.
  • Learn about the properties of cyclic groups and their classification.
  • Explore examples of abelian groups and their subgroup structures.
  • Investigate the implications of group order on isomorphism classes.
USEFUL FOR

This discussion is beneficial for students of abstract algebra, particularly those studying group theory, as well as educators seeking to clarify the relationship between group order and structure. It is also relevant for mathematicians interested in the applications of Sylow theorems.

JojoF
Messages
4
Reaction score
1

Homework Statement


Let ##G## be a group of order ##2p## with p a prime and odd number.

a) We suppose ##G## as abelian. Show that ##G \simeq \mathbb{Z}/2p\mathbb{Z}##

Homework Equations

The Attempt at a Solution


Intuitively I see why but I would like some suggestion of what trajectory I could take to prove this.

I proved in an earlier problem that all groups with a prime order is a cyclic group.
I am sure it is a Sylow theorems problem.

Thanks!
 
Physics news on Phys.org
JojoF said:

Homework Statement


Let ##G## be a group of order ##2p## with p a prime and odd number.

a) We suppose ##G## as abelian. Show that ##G \simeq \mathbb{Z}/2p\mathbb{Z}##

Homework Equations

The Attempt at a Solution


Intuitively I see why but I would like some suggestion of what trajectory I could take to prove this.

I proved in an earlier problem that all groups with a prime order is a cyclic group.
I am sure it is a Sylow theorems problem.

Thanks!

A (possible) hint: show that ##G## is cyclic and the result will follow because any two cyclic groups of the same order are isomorphic.
 
The assumption, that ##G## is Abelian is crucial, as the example with ##p=3## and ##Sym(3)## shows, so this has to play a role in your proof. E.g. all subgroups are automatically normal. I would concentrate on the first Sylow theorem.
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
Replies
5
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
5
Views
2K