Proving G is Abelian: A Group Theory Case

Click For Summary
SUMMARY

The discussion focuses on proving that a finite group G of order n, where n is not divisible by 3, is abelian under the condition that (ab)^3 = a^3 b^3 for all elements a, b in G. The proof utilizes the fact that since 3 does not divide n, the equation un + 3v = 1 holds, leading to the conclusion that G can be expressed as G = {y^3 | y is in G}. The goal is to demonstrate that ab = ba for all elements a and b in G, with a specific manipulation of the group operation provided as a key step in the proof.

PREREQUISITES
  • Understanding of group theory concepts, particularly finite groups.
  • Familiarity with the properties of exponents in group operations.
  • Knowledge of the implications of group order and divisibility.
  • Experience with proving group properties, specifically abelian characteristics.
NEXT STEPS
  • Study the implications of group order in finite groups, particularly regarding divisibility.
  • Learn about the structure and properties of abelian groups in group theory.
  • Explore the use of exponentiation in group operations and its applications in proofs.
  • Investigate additional examples of proving group properties using similar techniques.
USEFUL FOR

Mathematicians, students of abstract algebra, and anyone interested in group theory, particularly those focusing on the properties of finite groups and abelian structures.

mansi
Messages
61
Reaction score
0
seeing lots of group theory here after a really long time...
let G be a finite group of order n, where n is not divisible by 3. suppose
(ab)^3 = a^3 b^3 ,for a, b in G . prove that G is abelian.
 
Physics news on Phys.org
i guess i must( or rather i am supposed to) add my thought process...
since 3 does not divide n (n,3)=1 so we have un +3v=1...now for any x in G, x = x^(un+3v)= x^3v.
so G ={y^3 / y is in G}...using this i think we're supposed to show that ab=ba for all a in G. here's where I'm stuck.
 
It's frequently useful to reverse what's inside an exponent. For example:

b * (ab)^3 * a = b(ababab)a = (ba)^4
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 26 ·
Replies
26
Views
2K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 14 ·
Replies
14
Views
4K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K