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2 votes
1 answer
73 views

Why should a splitting field of a polynomial over $\mathbb{F}_p[X]$ be a cyclotomic extension?

I have just been doing a Galois theory exercise and one part of the exercise requires me to explain why, if $f \in \mathbb{F}_p[X]$ is a polynomial of degree $n$, its splitting field $L$ is a ...
Featherball's user avatar
0 votes
1 answer
201 views

Splitting field of $x^3 +x +1$ over $\mathbb F_{11}$

This is a HW problem for an algebra course. Determine the splitting field of $f(x)=x^3+x+1$ over $\mathbb F_{11}$. I tried to use the answers from this question and this question to help me, but want ...
pyridoxal_trigeminus's user avatar
2 votes
0 answers
161 views

Splitting field of $x^8-1$ over $\mathbb{F}_2 ,\mathbb{F}_3,\mathbb{F}_{16}$

Find the splitting field of $f(x)=x^8-1$ over $\mathbb{F}_2$, $\mathbb{F}_3$ and $\mathbb{F}_{16}$. I tried this: We claim that the field with $q=p^m$ elements is unique. A field with $q$ elements is ...
Roozbeh Ranjbar's user avatar
1 vote
2 answers
319 views

Let $f ∈ \mathbb{F}_p[x]$ be an irreducible polynomial. Show that $f$ splits into linear factors in $\mathbb{F}_{p^{\deg(f)}}$.

As the title explains, I'm trying to answer the following question Let $f ∈ \mathbb{F}_p[x]$ be an irreducible polynomial. Show that $f$ splits into linear factors in $\mathbb{F}_{p^{\deg(f)}}$. ...
ganar's user avatar
  • 23
3 votes
2 answers
370 views

Degree of splitting field of $x^6+tx^3+t$ in $\mathbb{F}_3(t)[x]$

I'm trying to find the degree splitting field of $x^6+tx^3+t$ in $\mathbb{F}_3(t)[x]$. After substituting $z= x^3$, and using the qudratic formula, and thensubstituting $x$ back in, I get the roots $$...
jackson5's user avatar
  • 1,624
0 votes
1 answer
65 views

If $f$ has $\deg(f)$ distince roots whose order are the same, then is $f$ irreducible?

P1:Let $f$ be a polynomial over finite field $F$ and $n$ be the degree of $f$. Suppose $f$ has $n$ distince roots $\alpha_i$, over its splitting field $E$, $i=1,2,\ldots,n$ and the orders of $\alpha_i$...
Zongxiang Yi's user avatar
  • 1,174
1 vote
1 answer
774 views

Does an irreducible polynomial over a finite field F divide the splitting fields polynomials for which F is a subfield?

I read somewhere that : A subfield of $F_{p^n}$ has order $p^d$ where $d\mid n$, and there is one such subfield for each $d$. Let $q = p^n$ We have that any irreducible polynomial of degree $n$ ...
Donno's user avatar
  • 153
1 vote
2 answers
128 views

Different Representations of GF(8)

Can anyone point me in the right direction with the following problem? Given that $$GF(8)=\frac{Z_{2}}{x^3+x^2+1}= \frac{Z_{2}}{x^3+x+1}$$ Find $\beta$ as a function of $\alpha$ , where $\alpha$ is ...
trek26's user avatar
  • 101
0 votes
0 answers
838 views

Show that 2 splitting fields are isomoprhic.

Let $f(x) = x^3 + 2x + 1, g(x) = x^3 + x^2 + x + 2$ be polynomials over $\mathbb{Z}_3$, let $F$ be a splitting field of $f(x)$ and $E$ be a splitting field of $g(x)$. Since $f, g$ are irreducible over ...
Pan Miroslav's user avatar
0 votes
2 answers
616 views

Find the splitting field of a product of two polynomials

I have trouble finding the answer to his problem and I would really appreciate an answer to this problem. Problem : Find the splitting fields of f(x)*g(x) for f(x) = $x^3+x+1$ and g(x) = $x^3+x^2+1$ ...
Christ Schwabe's user avatar
1 vote
1 answer
279 views

Prove that polynomial doesn't have multiple roots over a splitting field

Let $p$ be a prime number, $m, s \in \mathbb{N}$ and $q = p^s$. Let $f(t) = \sum_{i=0}^m \lambda_i t^{p^{i}} \in \mathbb{F}_q[t]$. I'm asked to prove that $f(a\alpha+b\beta) = af(\alpha)+bf(\beta)$, ...
amrsa's user avatar
  • 13.1k
1 vote
1 answer
313 views

Compute the degree of the splitting field

I need to compute the degree of the splitting field of the polynomial $X^{4}+X^{3}+X^{2}+X+1$ over the field $\mathbb{F}_{3}$. Quite honestly I don't really know where to begin, I know the polynomial ...
ENAFMTH's user avatar
  • 453