Algebra help - primitive roots and minimal polynomials

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SUMMARY

This discussion focuses on finding a primitive root in the field F3[x]/(x^2 + 1) and determining its minimal polynomial. A primitive root is defined as an element x in a field such that x^n = 1 for some n, with no smaller k satisfying x^k = 1. The participants clarify that the order of the polynomial is crucial, and the minimal polynomial p(x) of the primitive root must be identified. The discussion emphasizes the relationship between primitive roots and polynomial orders in finite fields.

PREREQUISITES
  • Understanding of finite fields, specifically F3.
  • Knowledge of polynomial algebra, particularly minimal polynomials.
  • Familiarity with the concept of primitive roots in field theory.
  • Basic understanding of isomorphism in algebraic structures.
NEXT STEPS
  • Study the properties of finite fields, focusing on F3 and its elements.
  • Learn how to compute minimal polynomials in polynomial rings.
  • Explore the concept of isomorphism in algebra, particularly in relation to finite fields.
  • Investigate the relationship between primitive roots and polynomial orders in more depth.
USEFUL FOR

Students and educators in abstract algebra, particularly those studying finite fields, polynomial algebra, and the properties of primitive roots.

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Homework Statement



(a) Find a primitive root β of F3[x]/(x^2 + 1).
(b) Find the minimal polynomial p(x) of β in F3[x].
(c) Show that F3[x]/(x^2 + 1) is isomorphic to F3[x]/(p(x)).


The Attempt at a Solution



I am completely lost on this one :confused:
 
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So for the first one, you need to find a primitive root in \mathbb{F}_3[x]/(x^2+1)
Can you tell us what a primitive root is?
Can you find any root (not just primitive) in our field? To find this, take an arbitrary element a+bx in our field. Can you find a, b and n such that (a+bx)^n=1?
 
From what i understand, a primitive root is a value that when taking to the power of the order of the polynomial, you will get 1 (mod 3 for this example) I don't know if this is right, but i get x^2+1 as a primitive root. Does that make sense. The order of the polynomial is 2, so (x^2+1)^2 = 1
 
Wow, I have an entirely different definition of primitive root...
I have this: Let F be a field, then a nth root is an element x in F such that x^n=1 for some n&gt;0. The nth root x is called primitive if there is no k<n such that x^k=1.

Does this make any sense to you? Or do you understand something completely different in the term root?
 
That makes sense, but from what i thought i understood, the n is usually the order (or degree) of the polynomial. But i might be wrong.
 
I don't really understand what polynomials have to do with this. The only thing I can image is that a nth root of unity is a root of the polynomial X^n-1.

Can you give me the exact definition in your course? I really want to know if we're talking about thesame thing here...
 

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