Given a positive integer $n$. How to find a Galois extension $K/F$ such that $Gal(K/F)=S_n$?
With the restriction $F=\mathbb{Q}$, this is the Inverse Galois Problem. But if we are allowed to choose $F$ and $K$, I suspect there is a simpler example.
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5http://math.stackexchange.com/questions/165675/constructing-a-galois-extension-field-with-galois-group-s-n?rq=1 – John Myers Jun 19 '13 at 05:55
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How about $F=\mathbb Q(T_1, \ldots, T_{n-1})$ and $K=\mathbb F[X]/(X^n+T_{n-1}X^{n-1}+\ldots +T_0)$?
Hagen von Eitzen
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Why is $K$ Galois over $F$? Maybe the construction needs to be done several times to get a Galois extension. Or simply take $K$ to be the splitting field of $X^n+T_{n-1}X^{n-1}+\cdots+T_0$ over $F$? – Jun 19 '13 at 06:02
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Do you know the concept of general polynomials? you can read the online course notes by J.S.Milne : http://www.jmilne.org/math/CourseNotes/FT.pdf, here you will find your answer clearly.
Hajime_Saito
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