Algebra help - primitive roots and minimal polynomials

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The discussion revolves around finding a primitive root in the field F3[x]/(x^2 + 1) and understanding its minimal polynomial. Participants express confusion over the definition of a primitive root, with one suggesting that it should satisfy (a + bx)^n = 1 for some n. There is a debate about the relationship between primitive roots and polynomials, particularly regarding the order of the polynomial and roots of unity. Clarification is sought on the exact definition of primitive roots as taught in their course. The conversation highlights the complexities of algebraic structures and the need for a clear understanding of foundational concepts.
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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...
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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