Quartic Fields and Radical Extensions
โ Scribed by Huah Chu; Ming-chang Kang
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 224 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0747-7171
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โฆ Synopsis
Let K be a field and K(ฮฑ) be an extension field of K. If [K(ฮฑ) : K] = 3, char K = 3, and the minimal polynomial of ฮฑ over Kang (2000, Am. Math. Monthly, 107, 254-256)
In this paper, we prove a similar result when [K(ฮฑ) : K] = 4, char K = 2, and the minimal polynomial of ฮฑ over K is T 4 -uT 2 -vT -w โ K[T ] with v = 0 : K(ฮฑ) is a radical extension of K if and only if the following system of polynomial equations is solvable in K, 64X 3 -32uX 2 + (4u 2 + 16w)X -v 2 = 0 and 64wX 2 -(32uw -3v 2 )X + (4u 2 w + 16w 2 -uv 2 ) -Y 2 = 0. The situation when v = 0 will also be solved.
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