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5:19 AM
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Q: Prove the automorphism preserves the relation among roots.

PropositionXLet $F$ be a field and let $f(x)\in F[x]$. Denote the splitting field of $f(x)$ by $E$. Denote the roots of $f(x)$ by $\alpha_1,...,\alpha_n$. A polynomial $g(x_1,...,x_n) ∈ F[x_1,...,x_n]$ gives an relation between the roots if $g(α_1,...,α_n) = 0.$ Now let $σ\in Aut_F(E)$, and let $τ$ denote...

1
Q: Prove $Aut_F(E)$ is isomorphic to a subgroup of $Perm(X_1)×···×Perm(X_r)$

PropositionXLet F be a field. Let $f(x) ∈ F[x]$ be a nonzero polynomial, let $E$ be a splitting field for $f(x)$ over $F$, and let $X$ denote the set of roots of $f(x)$ in E Let $f(x)\in F[x]$, and suppose $f(x) = f_1(x)···f_r(x)$ is the factorization of $f(x)$ into irreducible polynomials in $F[x]$. For each...

0
Q: Categorical meaning of the two definitions of $\pi_n(X)$

Vincenzo ZaccaroI know that the higher homotopy groups $\pi_n(X)$ can be defined in two way. Homotopy classes of the continuos maps $(I^n,\partial I^n)\longrightarrow (X,x_0)$. Homotopy classes of the continuos maps $(S^n,s_0)\longrightarrow (X,x_0)$. These two ways to define the higher homotopy groups are e...

 
 
6 hours later…
10:52 AM
It seems that the tag is already more-or-less established (150 questions). So it would be good to have it at least on most important questions about transposed matrices. I am not sure which of the 5 tags on Determinant of transpose? could be removed and replaced by .
35
Q: Determinant of transpose?

dfg$$\det(A^T) = \det(A)$$ Using the geometric definition of the determinant as the area spanned by the columns could someone give a geometric interpretation of the property? Thanks!

 
 
1 hour later…
11:56 AM
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A: Do we need separate tags for (betting) and (gambling)?

arjafiI have just created a betting → gambling synonym, and merged the former into the latter. I'm not exactly sold on the usefulness of either tag, but for the time being I guess they are basically talking about the same thing.

It was handled some 40 days after I flagged it, which is probably record for my flags. But I have to say that the mods usually handle flags rather quickly.
 
12:29 PM
> I'm not exactly sold on the usefulness of either tag, but for the time being I guess they are basically talking about the same thing.
Using the query from arjafi's answer I get these as the oldest questions with tag: data.stackexchange.com/math/query/542457/…
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Q: Does variance do any good to gambling game makers?

VictorPeople always like to evaluate the variance, but is there any way for variance to be interesting to the gambling game makers? In another word, what is a pratical gambling game that involving some distributions that is relating to variance other than the normal distribution?

So probably created there. The second result from the query is a question posted by the same user: What is the formal mathematical relationship between the variance and the odds that the gambler who has smaller budget here?
Anyway, that tag has been around since 2013.
 
 
1 hour later…
1:33 PM
3
Q: A finitely axiomatizable consistent second-order theory without a model

M. WinterThe completeness theorem fails for second-order logic. This question has some nice examples of consistent second-order theories without models. But non of them is finitely axiomatizable, at least those examples use infinitely many axioms. Are there consistent finitely axiomatizable second-ord...

Doesn't this fall under more general ?
 
 
9 hours later…
11:01 PM
One of the rare cases where seems to actually fit the question: Why is it forbidden to use in this inductive step?
 

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