Abstract Algebra: Proving/Disproving |a|=|b| if |a^2|=|b^2|

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SUMMARY

The discussion centers on the mathematical problem of proving or disproving the statement that if |a^2|=|b^2|, then |a|=|b|. The user presents a counterexample using the group Z20, where a=2 and b=4, demonstrating that |a|=10 and |b|=5, while |a^2|=|b^2|=5. The user acknowledges that this counterexample does not apply universally across all groups and seeks a more general solution, suggesting that the statement may hold true in specific cases, such as in the group Z3.

PREREQUISITES
  • Understanding of group theory and group orders
  • Familiarity with the properties of the cyclic group Z20
  • Knowledge of counterexamples in mathematical proofs
  • Basic concepts of abstract algebra
NEXT STEPS
  • Research the properties of cyclic groups, specifically Z3 and Z20
  • Explore the concept of group order and its implications in abstract algebra
  • Study counterexamples in mathematical conjectures
  • Investigate the relationship between element orders and their squares in various groups
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Students of abstract algebra, mathematicians exploring group theory, and anyone interested in the nuances of mathematical proofs and counterexamples.

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Homework Statement



If |a^2|=|b^2|, prove or disprove that |a|=|b|.

Homework Equations


The hint I was given is that let a be an element of order 4n+2 and let the order of b=a2


The Attempt at a Solution


I can disprove this by looking at examples, such as in the group Z20 with letting a =2 and b=4, the |a|=10 and |b|=5, but |a^2|=5 and |b^2|=5. But I know that this does not disprove it for all groups, I need a more general solution. If anyone can help me on this it would be great.
 
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I'm going to go on a limb and say the statement is true for some groups (for example in Z3). When they say to disprove a conjecture, all that means is find a counterexample.
 

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