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Abel–Ruffini theorem

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3241:, who sent him a letter saying: "Your memoir on the general solution of equations is a work which I have always believed should be kept in mind by mathematicians and which, in my opinion, proves conclusively the algebraic unsolvability of general equations of higher than fourth degree." However, in general, Ruffini's proof was not considered convincing. Abel wrote: "The first and, if I am not mistaken, the only one who, before me, has sought to prove the impossibility of the algebraic solution of general equations is the mathematician Ruffini. But his memoir is so complicated that it is very difficult to determine the validity of his argument. It seems to me that his argument is not completely satisfying." 3219: 3802:. While Cauchy either did not notice Ruffini's assumption or felt that it was a minor one, most historians believe that the proof was not complete until Abel proved the theorem on natural irrationalities, which asserts that the assumption holds in the case of general polynomials. The Abel–Ruffini theorem is thus generally credited to Abel, who published a proof compressed into just six pages in 1824. (Abel adopted a very terse style to save paper and money: the proof was printed at his own expense.) A more elaborated version of the proof would be published in 1826. 3215:, he wrote "After the labors of many geometers left little hope of ever arriving at the resolution of the general equation algebraically, it appears more and more likely that this resolution is impossible and contradictory." And he added "Perhaps it will not be so difficult to prove, with all rigor, the impossibility for the fifth degree. I shall set forth my investigations of this at greater length in another place." Actually, Gauss published nothing else on this subject. 3201:. This innovative work by Lagrange was a precursor to Galois theory, and its failure to develop solutions for equations of fifth and higher degrees hinted that such solutions might be impossible, but it did not provide conclusive proof. The first person who conjectured that the problem of solving quintics by radicals might be impossible to solve was 319:. With modern computers and programs, deciding whether a polynomial is solvable by radicals can be done for polynomials of degree greater than 100. Computing the solutions in radicals of solvable polynomials requires huge computations. Even for the degree five, the expression of the solutions is so huge that it has no practical interest. 3817:
a memoir on his theory of solvability by radicals, which was ultimately rejected in 1831 as being too sketchy and for giving a condition in terms of the roots of the equation instead of its coefficients. Galois was aware of the contributions of Ruffini and Abel, since he wrote "It is a common truth,
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The proof also, as it was discovered later, was incomplete. Ruffini assumed that all radicals that he was dealing with could be expressed from the roots of the polynomial using field operations alone; in modern terms, he assumed that the radicals belonged to the splitting field of the polynomial. To
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might be soluble, with a special formula for each equation." However, the existence of specific equations that cannot be solved in radicals seems to be a consequence of Abel's proof, as the proof uses the fact that some polynomials in the coefficients are not the zero polynomial, and, given a finite
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refers also to the slightly stronger result that there are equations of degree five and higher that cannot be solved by radicals. This does not follow from Abel's statement of the theorem, but is a corollary of his proof, as his proof is based on the fact that some polynomials in the coefficients of
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Proving that the general quintic (and higher) equations were unsolvable by radicals did not completely settle the matter, because the Abel–Ruffini theorem does not provide necessary and sufficient conditions for saying precisely which quintic (and higher) equations are unsolvable by radicals. Abel
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that is a product of disjoint cycles of lengths 2 and 3 (in general, when a monic integer polynomial reduces modulo a prime to a product of distinct monic irreducible polynomials, the degrees of the factors give the lengths of the disjoint cycles in some permutation belonging to the Galois group);
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in 1845. When Wantzel published it, he was already aware of the contributions by Galois and he mentions that, whereas Abel's proof is valid only for general polynomials, Galois' approach can be used to provide a concrete polynomial of degree 5 whose roots cannot be expressed in radicals from its
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Abel's proof of the theorem does not explicitly contain the assertion that there are specific equations that cannot be solved by radicals. Such an assertion is not a consequence of Abel's statement of the theorem, as the statement does not exclude the possibility that "every particular
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The Abel–Ruffini theorem proves that this is impossible. However, this impossibility does not imply that a specific equation of any degree cannot be solved in radicals. On the contrary, there are equations of any degree that can be solved in radicals. This is the case of the equation
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From the 16th century to beginning of the 19th century, the main problem of algebra was to search for a formula for the solutions of polynomial equations of degree five and higher, hence the name the "fundamental theorem of algebra". This meant a
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as a generic equation. This finishes the proof that the Galois group of a general equation is the symmetric group, and thus proves the original Abel–Ruffini theorem, which asserts that the general polynomial equation of degree
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Conversely, if one has such a sequence of fields, the equation is solvable in terms of radicals. For proving this, it suffices to prove that a normal extension with a cyclic Galois group can be built from a succession of
331:. However, Galois theory allows a better understanding of the subject, and modern proofs are generally based on it, while the original proofs of the Abel–Ruffini theorem are still presented for historical purposes. 3813:, "The proofs of Ruffini and of Abel were soon superseded by the crowning achievement of this line of research: Galois' discoveries in the theory of equations." In 1830, Galois (at the age of 18) submitted to the 451: 3830:
accompanied by some of his own explanations. Prior to this publication, Liouville announced Galois' result to the academy in a speech he gave on 4 July 1843. A simplification of Abel's proof was published by
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So, if one starts from a solution in terms of radicals, one gets an increasing sequence of fields such that the last one contains the solution, and each is a normal extension of the preceding one with a
374:. Such an expression may be viewed as the description of a computation that starts from the coefficients of the equation to be solved and proceeds by computing some numbers, one after the other. 3211:(which would be published only in 1801) that "there is little doubt that this problem does not so much defy modern methods of analysis as that it proposes the impossible". The next year, in his 2246: 2134: 1702: 3822:
cannot be solved by radicals... this truth has become common (by hearsay) despite the fact that geometers have ignored the proofs of Abel and Ruffini..." Galois then died in 1832 and his paper
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for degree four, were found during the 16th century. At that time a fundamental problem was whether equations of higher degree could be solved in a similar way.
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began the groundwork that unified the many different methods that had been used up to that point to solve equations, relating them to the theory of groups of
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quintic is solvable in radicals if and only, when its coefficients are substituted in Cayley's resolvent, the resulting sextic polynomial has a
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Teoria generale delle equazioni, in cui si dimostra impossibile la soluzione algebraica delle equazioni generali di grado superiore al quarto
4184: 4051: 3877: 397: 4674: 3218: 3999: 4547: 4223: 3960:"Mémoire sur les équations algébriques, ou l'on démontre l'impossibilité de la résolution de l'équation générale du cinquième degré" 381:
that contains all numbers that have been computed so far. This field is changed only for the steps involving the computation of an
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that allows deciding, for any given equation, whether it is solvable in radicals. This was purely theoretical before the rise of
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An algebraic solution of the initial polynomial equation exists if and only if there exists such a sequence of fields such that
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in 1799. He sent his proof to several mathematicians to get it acknowledged, amongst them Lagrange (who did not reply) and
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The preceding section shows that an equation is solvable in terms of radicals if and only if the Galois group of its
201:, was asserted during the 17th century, but completely proved only at the beginning of the 19th century. This is the 1765:, this equation is not solvable in radicals. In view of the preceding sections, this results from the fact that the 4664: 4583: 4352: 4006: 3966: 335: 334:
The proofs based on Galois theory comprise four main steps: the characterization of solvable equations in terms of
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Riflessioni intorno alla soluzione delle equazioni algebraiche generali opuscolo del cav. dott. Paolo Ruffini ...
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is not solvable if its degree is five or higher; and the existence of polynomials with a symmetric Galois group.
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number of polynomials, there are values of the variables at which none of the polynomials takes the value zero.
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The impossibility of solving in degree five or higher contrasts with the case of lower degree: one has the
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of degree six whose coefficients are polynomials in the coefficients of a generic quintic. A specific
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Fieker, Claus; Klüners, Jürgen (2014), "Computation of Galois groups of rational polynomials",
3481: 2646: 251: 4634: 4614: 4543: 4456: 4421: 4390: 4341: 4219: 4180: 4047: 3995: 3955: 3712: 1705: 1424: 1253: 941: 724:, which are fundamental for the theory, one must refine the sequence of fields as follows. If 179: 156: 81: 31: 1819:, where the splitting field is the smallest field containing all the roots of the equation). 1423:, the symmetric group and all its subgroups are solvable. This explains the existence of the 818: 727: 4626: 4596: 4561: 4431: 4417: 4300: 4229: 4190: 4176: 4148: 4124: 4085: 3918: 3886: 3827: 3166: 2533: 2330: 721: 300: 58: 4557: 4320: 4144: 4097: 3906: 3570: 3543: 3516: 3338: 3309: 2905: 2498: 2471: 2440: 2287: 2251: 1175: 855: 791: 760: 693: 4565: 4553: 4448: 4435: 4316: 4233: 4194: 4152: 4140: 4093: 3922: 3902: 3840: 3810: 3597: 3178: 3041: 1812: 1774: 1755: 1432: 1291: 1287: 1215: 1170: 1147: 1139: 371: 351: 191: 183: 164: 4536:
Abel's Theorem in Problems and Solutions: Based on the Lectures of Professor V. I. Arnold
3306:, one of its roots (all of them, actually) can be expressed as the sum of a cube root of 2063:{\displaystyle P(x)=x^{n}+b_{1}x^{n-1}+\cdots +b_{n-1}x+b_{n}=(x-x_{1})\cdots (x-x_{n}).} 992:
and the subgroups of the Galois group of the extension. This correspondence maps a field
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the equation are not the zero polynomial. This improved statement follows directly from
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Kiernan, B. Melvin (1971), "The Development of Galois Theory from Lagrange to Artin",
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Topological Galois Theory: Solvability and Unsolvability of Equations in Finite Terms
4579:"Short Proof of Abel's Theorem that 5th Degree Polynomial Equations Cannot be Solved" 4328: 4268: 3914: 3222: 2586: 1436: 1428: 1337: 1159: 328: 312: 187: 160: 92: 17: 4510: 3245:
see why this is really an extra assumption, consider, for instance, the polynomial
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The fact that every polynomial equation of positive degree has solutions, possibly
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Testing whether a specific quintic is solvable in radicals can be done by using
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Abel's Proof: An Essay on the Sources and Meaning of Mathematical Unsolvability
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and is thus fixed by all these automorphisms. It follows that the Galois group
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is not solvable, and that there are polynomials with symmetric Galois groups.
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is solvable (the term "solvable group" takes its origin from this theorem).
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Ayoub, Raymond G. (1980), "Paolo Ruffini's Contributions to the Quintic",
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be its Galois group, which acts faithfully on the set of complex roots of
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be new indeterminates, aimed to be the roots, and consider the polynomial
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means that the coefficients of the equation are viewed and manipulated as
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involving only the coefficients of the equation, and the operations of
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So, for proving the Abel–Ruffini theorem, it remains to show that the
4249:(1869) , "Réflexions sur la résolution algébrique des équations", in 3824:
Mémoire sur les conditions de resolubilité des équations par radicaux
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is the simplest equation that cannot be solved in radicals, and that
4128: 446:{\displaystyle F_{0}\subseteq F_{1}\subseteq \cdots \subseteq F_{k}} 1336:(that is, it does not have any nontrivial normal subgroup) and not 152:
polynomials of degree five or higher cannot be solved in radicals.
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of the Abel–Ruffini theorem, which served as a starting point for
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coefficients. The original Abel–Ruffini theorem asserts that, for
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was working on a complete characterization when he died in 1829.
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At each step of the computation, one may consider the smallest
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Arnold's Elementary Proof of the Insolvability of the Quintic
2944: 2736: 3091: 3060: 3019: 2704: 2407: 1832: 1786: 1578:{\displaystyle x^{n}+a_{1}x^{n-1}+\cdots +a_{n-1}x+a_{n}=0,} 1381: 1350: 1311: 1265: 1227: 342:
between subfields of a given field and the subgroups of its
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allows approximating the solutions to any desired accuracy.
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Equations of degree 5 or higher cannot be solved by radicals
370:(addition, subtraction, multiplication, and division), and 3826:
remained unpublished until 1846, when it was published by
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is not solvable in radicals, as will be explained below.
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today, that the general equation of degree greater than
3009:. Because 5 is prime, any transposition and 5-cycle in 295:, all of whose solutions can be expressed in radicals. 3744: 3715: 3693: 3629: 3600: 3573: 3546: 3519: 3484: 3446: 3408: 3370: 3341: 3312: 3251: 3118: 3087: 3050: 3015: 2969: 2939: 2908: 2883: 2841: 2761: 2731: 2700: 2649: 2597: 2536: 2501: 2474: 2443: 2403: 2363: 2333: 2290: 2254: 2191: 2142: 2079: 1911: 1862: 1828: 1782: 1714: 1647: 1594: 1485: 1377: 1346: 1307: 1261: 1223: 1178: 1093: 1037: 1002: 970: 885: 858: 821: 794: 763: 730: 696: 663: 605: 564: 502: 462: 400: 362:
An algebraic solution of a polynomial equation is an
254: 104: 3205:, who wrote in 1798 in section 359 of his book 1142:(the smallest field that contains all the roots) is 4257:, vol. III, Gauthier-Villars, pp. 205–421 2587:
Galois theory § A non-solvable quintic example
2241:{\displaystyle K=\mathbb {Q} (b_{1},\ldots ,b_{n})} 2129:{\displaystyle H=\mathbb {Q} (x_{1},\ldots ,x_{n})} 1697:{\displaystyle F=\mathbb {Q} (a_{1},\ldots ,a_{n})} 93:
Galois theory § A non-solvable quintic example
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Tommaso d'Aquino 391:So, an algebraic solution produces a sequence 4407: 4405: 4163: 4161: 1158:. (Solvable groups are commonly defined with 8: 4488:Journal de Mathématiques Pures et Appliquées 4346:"Sur la resolution algébrique des équations" 3941:(in Italian). presso la Societa Tipografica. 2435:fundamental theorem of symmetric polynomials 1164:fundamental theorem of finite abelian groups 307:Soon after Abel's publication of its proof, 1856:it is simpler to start from the roots. Let 1162:instead of cyclic quotient groups, but the 4363:(in French), vol. II (2nd ed.), 4284: 4282: 4068:LMS Journal of Computation and Mathematics 2828:{\displaystyle (x^{2}+x+1)(x^{3}+x^{2}+1)} 2136:be the field of the rational fractions in 4381:(2015), "The Idea Behind Galois Theory", 4079: 4030: 4028: 4017:(in French), vol. I (2nd ed.), 3977:(in French), vol. I (2nd ed.), 3783: 3770: 3757: 3745: 3743: 3714: 3694: 3692: 3668: 3655: 3642: 3630: 3628: 3599: 3578: 3572: 3551: 3545: 3524: 3518: 3483: 3445: 3407: 3369: 3340: 3311: 3271: 3250: 3123: 3117: 3096: 3090: 3089: 3086: 3065: 3059: 3058: 3049: 3024: 3018: 3017: 3014: 2976: 2972: 2971: 2968: 2947: 2943: 2938: 2913: 2907: 2882: 2848: 2844: 2843: 2840: 2810: 2797: 2769: 2760: 2739: 2735: 2730: 2709: 2703: 2702: 2699: 2654: 2648: 2602: 2596: 2535: 2506: 2500: 2479: 2473: 2448: 2442: 2412: 2406: 2405: 2402: 2390:{\displaystyle \operatorname {Gal} (H/K)} 2376: 2362: 2338: 2332: 2295: 2289: 2253: 2229: 2210: 2199: 2198: 2190: 2166: 2147: 2141: 2117: 2098: 2087: 2086: 2078: 2048: 2023: 2001: 1979: 1954: 1944: 1931: 1910: 1886: 1867: 1861: 1837: 1831: 1830: 1827: 1815:of the equation that fix the elements of 1791: 1785: 1784: 1781: 1738: 1719: 1713: 1685: 1666: 1655: 1654: 1646: 1618: 1599: 1593: 1560: 1538: 1513: 1503: 1490: 1484: 1386: 1380: 1379: 1376: 1355: 1349: 1348: 1345: 1316: 1310: 1309: 1306: 1270: 1264: 1263: 1260: 1232: 1226: 1225: 1222: 1183: 1177: 1120:{\displaystyle \operatorname {Gal} (F/E)} 1106: 1092: 1064:{\displaystyle \operatorname {Gal} (F/K)} 1050: 1036: 1001: 974: 969: 903: 890: 884: 863: 857: 826: 820: 799: 793: 768: 762: 735: 729: 701: 695: 668: 662: 635: 620: 615: 610: 604: 563: 539: 520: 507: 501: 480: 467: 461: 437: 418: 405: 399: 259: 253: 109: 103: 2690:. Numbering the roots lets one identify 2468:, and thus that the map that sends each 1455:Polynomials with symmetric Galois groups 1083:fixed, and, conversely, maps a subgroup 650:{\displaystyle x_{i}^{n_{i}}\in F_{i-1}} 4205: 4203: 3990: 3988: 3950: 3948: 3870: 3868: 3866: 3864: 3860: 3233:The theorem was first nearly proved by 2694:with a subgroup of the symmetric group 1807:(this Galois group is the group of the 1638:. This is an equation defined over the 1292:Symmetric group § Normal subgroups 1021:{\displaystyle E\subseteq K\subseteq F} 4621:, Springer Monographs in Mathematics, 4451:(2009), "Galois Theory of Equations", 4412:Tignol, Jean-Pierre (2016), "Galois", 4455:, vol. 1 (2nd ed.), Dover, 4414:Galois' Theory of Algebraic Equations 4361:Œuvres Complètes de Niels Henrik Abel 4292:Archive for History of Exact Sciences 4173:Galois' Theory of Algebraic Equations 4015:Œuvres Complètes de Niels Henrik Abel 3975:Œuvres Complètes de Niels Henrik Abel 3878:Archive for History of Exact Sciences 3623:are all real and therefore the field 1822:For proving that the Galois group is 178:of degree two can be solved with the 7: 3074:{\displaystyle G={\mathcal {S}}_{5}} 2178:{\displaystyle x_{1},\ldots ,x_{n},} 551:{\displaystyle F_{i}=F_{i-1}(x_{i})} 358:Algebraic solutions and field theory 4038:(2015), "Historical Introduction", 2530:. This means that one may consider 2424:{\displaystyle {\mathcal {S}}_{n}.} 1895:{\displaystyle x_{1},\ldots ,x_{n}} 1849:{\displaystyle {\mathcal {S}}_{n},} 1747:{\displaystyle a_{1},\ldots ,a_{n}} 1627:{\displaystyle a_{1},\ldots ,a_{n}} 95:. Galois theory implies also that 4516:Nouvelles Annales de Mathématiques 3105:{\displaystyle {\mathcal {S}}_{5}} 3033:{\displaystyle {\mathcal {S}}_{5}} 2718:{\displaystyle {\mathcal {S}}_{5}} 1800:{\displaystyle {\mathcal {S}}_{n}} 1435:formulas, since a major result of 1395:{\displaystyle {\mathcal {S}}_{n}} 1364:{\displaystyle {\mathcal {A}}_{n}} 1325:{\displaystyle {\mathcal {A}}_{n}} 1279:{\displaystyle {\mathcal {A}}_{n}} 1241:{\displaystyle {\mathcal {S}}_{n}} 25: 3295:{\displaystyle P(x)=x^{3}-15x-20} 2570:cannot be solved in radicals for 3746: 3695: 3631: 3001:, the same principle shows that 2994:{\displaystyle \mathbb {F} _{3}} 2866:{\displaystyle \mathbb {F} _{2}} 1127:to the field of the elements of 311:introduced a theory, now called 84:, who provided a proof in 1824. 3227:Teoria generale delle equazioni 291:, and the equations defined by 4534:Alekseev, Valeriy B. (2004), 3789: 3750: 3674: 3635: 3610: 3604: 3494: 3488: 3459: 3450: 3421: 3412: 3383: 3374: 3261: 3255: 3112:is not solvable, the equation 3040:generate the whole group; see 2988: 2982: 2860: 2854: 2822: 2790: 2787: 2762: 2546: 2540: 2384: 2370: 2264: 2258: 2235: 2203: 2123: 2091: 2054: 2035: 2029: 2010: 1921: 1915: 1691: 1659: 1472:polynomial equation of degree 1114: 1100: 1058: 1044: 909: 896: 592:{\displaystyle i=1,\ldots ,k,} 545: 532: 489:{\displaystyle x_{i}\in F_{i}} 203:fundamental theorem of algebra 1: 4116:American Mathematical Monthly 3157:is not solvable in radicals. 1150:in the preceding one, with a 918:{\displaystyle K_{i}(x_{i}).} 182:, which has been known since 3702:{\displaystyle \mathbf {R} } 2956:{\displaystyle q{\bmod {3}}} 2748:{\displaystyle q{\bmod {2}}} 2522:is a field isomorphism from 2319:imply that every element of 964:of a normal field extension 47:Abel's impossibility theorem 3364:. On the other hand, since 3208:Disquisitiones Arithmeticae 3150:{\displaystyle x^{5}-x-1=0} 2629:{\displaystyle x^{5}-x-1=0} 788:, one introduces the field 683:{\displaystyle n_{i}>1.} 136:{\displaystyle x^{5}-x-1=0} 76:The theorem is named after 4691: 4675:Theorems about polynomials 4540:Kluwer Academic Publishers 3471:{\displaystyle P(-1)<0} 3433:{\displaystyle P(-2)>0} 3395:{\displaystyle P(-3)<0} 2584: 190:for degree three, and the 49:) states that there is no 29: 4631:10.1007/978-3-642-38871-2 4090:10.1112/S1461157013000302 3849:topological Galois theory 3815:Paris Academy of Sciences 3506:{\displaystyle P(5)>0} 3160: 2675:{\displaystyle x^{5}-x-1} 1340:. This implies that both 1203:Solvable symmetric groups 958:one to one correspondence 366:involving the four basic 280:{\displaystyle x^{n}-1=0} 61:or higher with arbitrary 3731:{\displaystyle 10\pm 5i} 2311:induce automorphisms of 1301:, the alternating group 456:of fields, and elements 30:Not to be confused with 3935:Ruffini, Paolo (1813). 3709:. But then the numbers 2877:contains a permutation 2397:is the symmetric group 1773:of the equation is the 1416:On the other hand, for 850:primitive root of unity 841:{\displaystyle F_{i-1}} 750:{\displaystyle F_{i-1}} 4247:Lagrange, Joseph-Louis 3796: 3732: 3703: 3681: 3617: 3588: 3561: 3534: 3507: 3472: 3434: 3396: 3358: 3329: 3296: 3230: 3151: 3106: 3075: 3034: 2995: 2957: 2923: 2891: 2867: 2829: 2749: 2719: 2676: 2630: 2559: 2558:{\displaystyle P(x)=0} 2516: 2489: 2458: 2425: 2391: 2351: 2350:{\displaystyle x_{i},} 2305: 2274: 2242: 2179: 2130: 2064: 1896: 1850: 1801: 1748: 1698: 1628: 1579: 1396: 1365: 1326: 1280: 1242: 1193: 1121: 1065: 1022: 986: 919: 873: 842: 809: 778: 751: 711: 684: 651: 593: 552: 490: 447: 293:cyclotomic polynomials 281: 137: 4251:Serret, Joseph-Alfred 4210:Pesic, Peter (2004), 3797: 3733: 3704: 3682: 3618: 3589: 3587:{\displaystyle r_{3}} 3562: 3560:{\displaystyle r_{2}} 3535: 3533:{\displaystyle r_{1}} 3508: 3473: 3435: 3397: 3359: 3357:{\displaystyle 10-5i} 3330: 3328:{\displaystyle 10+5i} 3297: 3239:Augustin-Louis Cauchy 3221: 3191:Joseph Louis Lagrange 3171:univariate polynomial 3152: 3107: 3076: 3035: 2996: 2958: 2924: 2922:{\displaystyle g^{3}} 2892: 2868: 2830: 2750: 2720: 2677: 2631: 2560: 2517: 2515:{\displaystyle b_{i}} 2495:to the corresponding 2490: 2488:{\displaystyle a_{i}} 2466:algebraic independent 2459: 2457:{\displaystyle b_{i}} 2426: 2392: 2352: 2306: 2304:{\displaystyle x_{i}} 2275: 2273:{\displaystyle P(x).} 2243: 2180: 2131: 2065: 1897: 1851: 1802: 1749: 1699: 1629: 1580: 1397: 1366: 1327: 1281: 1243: 1194: 1192:{\displaystyle S_{5}} 1122: 1066: 1023: 987: 954:Galois correspondence 948:Galois correspondence 920: 874: 872:{\displaystyle F_{i}} 843: 810: 808:{\displaystyle K_{i}} 779: 777:{\displaystyle n_{i}} 757:does not contain all 752: 717:contains a solution. 712: 710:{\displaystyle F_{k}} 685: 652: 594: 553: 491: 448: 368:arithmetic operations 350:; the proof that the 340:Galois correspondence 282: 138: 3742: 3713: 3691: 3627: 3616:{\displaystyle P(x)} 3598: 3571: 3544: 3517: 3482: 3444: 3406: 3368: 3339: 3335:with a cube root of 3310: 3249: 3203:Carl Friedrich Gauss 3116: 3085: 3048: 3013: 2967: 2937: 2906: 2881: 2839: 2759: 2729: 2698: 2647: 2595: 2534: 2499: 2472: 2441: 2401: 2361: 2331: 2288: 2252: 2189: 2140: 2077: 1909: 1860: 1826: 1780: 1712: 1645: 1592: 1483: 1445:solution in radicals 1375: 1344: 1305: 1259: 1221: 1176: 1091: 1035: 1000: 968: 883: 856: 852:, and one redefines 819: 792: 761: 728: 694: 661: 603: 562: 500: 460: 398: 317:electronic computers 252: 215:solution in radicals 176:Polynomial equations 102: 88:Abel–Ruffini theorem 55:polynomial equations 51:solution in radicals 43:Abel–Ruffini theorem 18:Abel-Ruffini theorem 4169:Tignol, Jean-Pierre 3199:Lagrange resolvents 1809:field automorphisms 1447:if and only if its 1441:polynomial equation 985:{\displaystyle F/E} 627: 4615:Khovanskii, Askold 4367:, pp. 217–243 4365:Grøndahl & Søn 4342:Abel, Niels Henrik 4305:10.1007/BF00327219 4255:Œuvres de Lagrange 4019:Grøndahl & Søn 3996:Abel, Niels Henrik 3979:Grøndahl & Søn 3956:Abel, Niels Henrik 3891:10.1007/BF00357046 3792: 3728: 3699: 3677: 3613: 3584: 3557: 3530: 3503: 3468: 3430: 3392: 3354: 3325: 3292: 3231: 3167:Cayley's resolvent 3161:Cayley's resolvent 3147: 3102: 3081:. Since the group 3071: 3030: 2991: 2963:is irreducible in 2953: 2919: 2887: 2863: 2825: 2745: 2715: 2672: 2626: 2555: 2512: 2485: 2454: 2421: 2387: 2347: 2325:symmetric function 2301: 2270: 2238: 2175: 2126: 2060: 1892: 1846: 1797: 1744: 1706:rational fractions 1694: 1624: 1575: 1392: 1361: 1322: 1276: 1238: 1189: 1131:that are fixed by 1117: 1061: 1018: 982: 942:radical extensions 915: 869: 838: 805: 774: 747: 707: 680: 647: 606: 589: 548: 486: 443: 277: 242:th root extraction 133: 4665:Niels Henrik Abel 4640:978-3-642-38870-5 4595:Goldmakher, Leo, 4462:978-0-486-47189-1 4427:978-981-4704-69-4 4396:978-1-4822-4582-0 4186:978-981-4704-69-4 4111:Rosen, Michael I. 4053:978-1-4822-4582-0 3845:topological proof 3738:cannot belong to 3687:is a subfield of 3304:Cardano's formula 3197:, in the form of 2890:{\displaystyle g} 2437:implies that the 1254:alternating group 722:normal extensions 657:for some integer 338:; the use of the 180:quadratic formula 157:quadratic formula 82:Niels Henrik Abel 16:(Redirected from 4682: 4644: 4643: 4611: 4605: 4604: 4603: 4592: 4586: 4580: 4575: 4569: 4568: 4531: 4525: 4524: 4503: 4497: 4496: 4484: 4476:Galois, Évariste 4472: 4466: 4465: 4449:Jacobson, Nathan 4445: 4439: 4438: 4418:World Scientific 4416:(2nd ed.), 4409: 4400: 4399: 4385:(4th ed.), 4375: 4369: 4368: 4350: 4338: 4332: 4331: 4286: 4277: 4276: 4265: 4259: 4258: 4243: 4237: 4236: 4207: 4198: 4197: 4177:World Scientific 4175:(2nd ed.), 4165: 4156: 4155: 4107: 4101: 4100: 4083: 4063: 4057: 4056: 4042:(4th ed.), 4032: 4023: 4022: 4021:, pp. 66–87 4004: 3992: 3983: 3982: 3981:, pp. 28–33 3964: 3952: 3943: 3942: 3932: 3926: 3925: 3872: 3828:Joseph Liouville 3821: 3801: 3799: 3798: 3793: 3788: 3787: 3775: 3774: 3762: 3761: 3749: 3737: 3735: 3734: 3729: 3708: 3706: 3705: 3700: 3698: 3686: 3684: 3683: 3678: 3673: 3672: 3660: 3659: 3647: 3646: 3634: 3622: 3620: 3619: 3614: 3593: 3591: 3590: 3585: 3583: 3582: 3566: 3564: 3563: 3558: 3556: 3555: 3539: 3537: 3536: 3531: 3529: 3528: 3512: 3510: 3509: 3504: 3477: 3475: 3474: 3469: 3439: 3437: 3436: 3431: 3401: 3399: 3398: 3393: 3363: 3361: 3360: 3355: 3334: 3332: 3331: 3326: 3301: 3299: 3298: 3293: 3276: 3275: 3156: 3154: 3153: 3148: 3128: 3127: 3111: 3109: 3108: 3103: 3101: 3100: 3095: 3094: 3080: 3078: 3077: 3072: 3070: 3069: 3064: 3063: 3039: 3037: 3036: 3031: 3029: 3028: 3023: 3022: 3004: 3000: 2998: 2997: 2992: 2981: 2980: 2975: 2962: 2960: 2959: 2954: 2952: 2951: 2928: 2926: 2925: 2920: 2918: 2917: 2901: 2896: 2894: 2893: 2888: 2876: 2872: 2870: 2869: 2864: 2853: 2852: 2847: 2834: 2832: 2831: 2826: 2815: 2814: 2802: 2801: 2774: 2773: 2754: 2752: 2751: 2746: 2744: 2743: 2724: 2722: 2721: 2716: 2714: 2713: 2708: 2707: 2693: 2689: 2685: 2681: 2679: 2678: 2673: 2659: 2658: 2642: 2635: 2633: 2632: 2627: 2607: 2606: 2581:Explicit example 2576: 2569: 2564: 2562: 2561: 2556: 2529: 2525: 2521: 2519: 2518: 2513: 2511: 2510: 2494: 2492: 2491: 2486: 2484: 2483: 2463: 2461: 2460: 2455: 2453: 2452: 2430: 2428: 2427: 2422: 2417: 2416: 2411: 2410: 2396: 2394: 2393: 2388: 2380: 2356: 2354: 2353: 2348: 2343: 2342: 2322: 2317:Vieta's formulas 2314: 2310: 2308: 2307: 2302: 2300: 2299: 2279: 2277: 2276: 2271: 2247: 2245: 2244: 2239: 2234: 2233: 2215: 2214: 2202: 2184: 2182: 2181: 2176: 2171: 2170: 2152: 2151: 2135: 2133: 2132: 2127: 2122: 2121: 2103: 2102: 2090: 2069: 2067: 2066: 2061: 2053: 2052: 2028: 2027: 2006: 2005: 1990: 1989: 1965: 1964: 1949: 1948: 1936: 1935: 1901: 1899: 1898: 1893: 1891: 1890: 1872: 1871: 1855: 1853: 1852: 1847: 1842: 1841: 1836: 1835: 1818: 1806: 1804: 1803: 1798: 1796: 1795: 1790: 1789: 1772: 1764: 1753: 1751: 1750: 1745: 1743: 1742: 1724: 1723: 1703: 1701: 1700: 1695: 1690: 1689: 1671: 1670: 1658: 1633: 1631: 1630: 1625: 1623: 1622: 1604: 1603: 1584: 1582: 1581: 1576: 1565: 1564: 1549: 1548: 1524: 1523: 1508: 1507: 1495: 1494: 1476:is the equation 1475: 1460:General equation 1422: 1412: 1401: 1399: 1398: 1393: 1391: 1390: 1385: 1384: 1370: 1368: 1367: 1362: 1360: 1359: 1354: 1353: 1331: 1329: 1328: 1323: 1321: 1320: 1315: 1314: 1300: 1286:as a nontrivial 1285: 1283: 1282: 1277: 1275: 1274: 1269: 1268: 1251: 1247: 1245: 1244: 1239: 1237: 1236: 1231: 1230: 1213: 1198: 1196: 1195: 1190: 1188: 1187: 1134: 1130: 1126: 1124: 1123: 1118: 1110: 1086: 1082: 1078: 1070: 1068: 1067: 1062: 1054: 1027: 1025: 1024: 1019: 995: 991: 989: 988: 983: 978: 924: 922: 921: 916: 908: 907: 895: 894: 878: 876: 875: 870: 868: 867: 847: 845: 844: 839: 837: 836: 814: 812: 811: 806: 804: 803: 783: 781: 780: 775: 773: 772: 756: 754: 753: 748: 746: 745: 716: 714: 713: 708: 706: 705: 689: 687: 686: 681: 673: 672: 656: 654: 653: 648: 646: 645: 626: 625: 624: 614: 598: 596: 595: 590: 557: 555: 554: 549: 544: 543: 531: 530: 512: 511: 495: 493: 492: 487: 485: 484: 472: 471: 452: 450: 449: 444: 442: 441: 423: 422: 410: 409: 385: 372:root extractions 301:quintic equation 290: 286: 284: 283: 278: 264: 263: 241: 186:. Similarly the 142: 140: 139: 134: 114: 113: 21: 4690: 4689: 4685: 4684: 4683: 4681: 4680: 4679: 4670:Solvable groups 4650: 4649: 4648: 4647: 4641: 4623:Springer-Verlag 4613: 4612: 4608: 4601: 4594: 4593: 4589: 4578: 4576: 4572: 4550: 4533: 4532: 4528: 4507:Wantzel, Pierre 4505: 4504: 4500: 4482: 4474: 4473: 4469: 4463: 4447: 4446: 4442: 4428: 4411: 4410: 4403: 4397: 4377: 4376: 4372: 4348: 4340: 4339: 4335: 4299:(1/2): 40–154, 4288: 4287: 4280: 4267: 4266: 4262: 4245: 4244: 4240: 4226: 4209: 4208: 4201: 4187: 4167: 4166: 4159: 4129:10.2307/2974763 4109: 4108: 4104: 4065: 4064: 4060: 4054: 4034: 4033: 4026: 4002: 3994: 3993: 3986: 3962: 3954: 3953: 3946: 3934: 3933: 3929: 3874: 3873: 3862: 3857: 3841:Vladimir Arnold 3819: 3811:Nathan Jacobson 3779: 3766: 3753: 3740: 3739: 3711: 3710: 3689: 3688: 3664: 3651: 3638: 3625: 3624: 3596: 3595: 3574: 3569: 3568: 3547: 3542: 3541: 3520: 3515: 3514: 3480: 3479: 3442: 3441: 3404: 3403: 3366: 3365: 3337: 3336: 3308: 3307: 3302:. According to 3267: 3247: 3246: 3187: 3163: 3119: 3114: 3113: 3088: 3083: 3082: 3057: 3046: 3045: 3016: 3011: 3010: 3002: 2970: 2965: 2964: 2935: 2934: 2909: 2904: 2903: 2899: 2879: 2878: 2874: 2842: 2837: 2836: 2806: 2793: 2765: 2757: 2756: 2727: 2726: 2701: 2696: 2695: 2691: 2687: 2683: 2650: 2645: 2644: 2640: 2598: 2593: 2592: 2589: 2583: 2571: 2567: 2532: 2531: 2527: 2523: 2502: 2497: 2496: 2475: 2470: 2469: 2444: 2439: 2438: 2404: 2399: 2398: 2359: 2358: 2334: 2329: 2328: 2320: 2312: 2291: 2286: 2285: 2250: 2249: 2225: 2206: 2187: 2186: 2162: 2143: 2138: 2137: 2113: 2094: 2075: 2074: 2044: 2019: 1997: 1975: 1950: 1940: 1927: 1907: 1906: 1882: 1863: 1858: 1857: 1829: 1824: 1823: 1816: 1813:splitting field 1783: 1778: 1777: 1775:symmetric group 1770: 1759: 1756:rational number 1734: 1715: 1710: 1709: 1681: 1662: 1643: 1642: 1614: 1595: 1590: 1589: 1556: 1534: 1509: 1499: 1486: 1481: 1480: 1473: 1462: 1457: 1417: 1407: 1378: 1373: 1372: 1347: 1342: 1341: 1308: 1303: 1302: 1295: 1288:normal subgroup 1262: 1257: 1256: 1249: 1224: 1219: 1218: 1216:symmetric group 1208: 1205: 1179: 1174: 1173: 1171:symmetric group 1140:splitting field 1132: 1128: 1089: 1088: 1084: 1080: 1076: 1033: 1032: 998: 997: 993: 966: 965: 950: 899: 886: 881: 880: 859: 854: 853: 822: 817: 816: 795: 790: 789: 764: 759: 758: 731: 726: 725: 697: 692: 691: 664: 659: 658: 631: 616: 601: 600: 560: 559: 535: 516: 503: 498: 497: 476: 463: 458: 457: 433: 414: 401: 396: 395: 383: 360: 352:symmetric group 348:solvable groups 325: 309:Évariste Galois 288: 255: 250: 249: 239: 207:Newton's method 192:quartic formula 173: 165:quartic formula 105: 100: 99: 45:(also known as 35: 28: 23: 22: 15: 12: 11: 5: 4688: 4686: 4678: 4677: 4672: 4667: 4662: 4652: 4651: 4646: 4645: 4639: 4606: 4587: 4570: 4548: 4526: 4498: 4467: 4461: 4440: 4426: 4401: 4395: 4370: 4333: 4278: 4269:Ruffini, Paolo 4260: 4238: 4224: 4199: 4185: 4157: 4123:(6): 495–505, 4102: 4074:(1): 141–158, 4058: 4052: 4024: 3984: 3944: 3927: 3885:(3): 253–277, 3859: 3858: 3856: 3853: 3836:coefficients. 3833:Pierre Wantzel 3791: 3786: 3782: 3778: 3773: 3769: 3765: 3760: 3756: 3752: 3748: 3727: 3724: 3721: 3718: 3697: 3676: 3671: 3667: 3663: 3658: 3654: 3650: 3645: 3641: 3637: 3633: 3612: 3609: 3606: 3603: 3581: 3577: 3554: 3550: 3527: 3523: 3502: 3499: 3496: 3493: 3490: 3487: 3467: 3464: 3461: 3458: 3455: 3452: 3449: 3429: 3426: 3423: 3420: 3417: 3414: 3411: 3391: 3388: 3385: 3382: 3379: 3376: 3373: 3353: 3350: 3347: 3344: 3324: 3321: 3318: 3315: 3291: 3288: 3285: 3282: 3279: 3274: 3270: 3266: 3263: 3260: 3257: 3254: 3186: 3183: 3162: 3159: 3146: 3143: 3140: 3137: 3134: 3131: 3126: 3122: 3099: 3093: 3068: 3062: 3056: 3053: 3027: 3021: 2990: 2987: 2984: 2979: 2974: 2950: 2946: 2942: 2916: 2912: 2902:also contains 2886: 2862: 2859: 2856: 2851: 2846: 2824: 2821: 2818: 2813: 2809: 2805: 2800: 2796: 2792: 2789: 2786: 2783: 2780: 2777: 2772: 2768: 2764: 2742: 2738: 2734: 2712: 2706: 2671: 2668: 2665: 2662: 2657: 2653: 2625: 2622: 2619: 2616: 2613: 2610: 2605: 2601: 2582: 2579: 2554: 2551: 2548: 2545: 2542: 2539: 2509: 2505: 2482: 2478: 2451: 2447: 2420: 2415: 2409: 2386: 2383: 2379: 2375: 2372: 2369: 2366: 2346: 2341: 2337: 2298: 2294: 2269: 2266: 2263: 2260: 2257: 2237: 2232: 2228: 2224: 2221: 2218: 2213: 2209: 2205: 2201: 2197: 2194: 2174: 2169: 2165: 2161: 2158: 2155: 2150: 2146: 2125: 2120: 2116: 2112: 2109: 2106: 2101: 2097: 2093: 2089: 2085: 2082: 2071: 2070: 2059: 2056: 2051: 2047: 2043: 2040: 2037: 2034: 2031: 2026: 2022: 2018: 2015: 2012: 2009: 2004: 2000: 1996: 1993: 1988: 1985: 1982: 1978: 1974: 1971: 1968: 1963: 1960: 1957: 1953: 1947: 1943: 1939: 1934: 1930: 1926: 1923: 1920: 1917: 1914: 1889: 1885: 1881: 1878: 1875: 1870: 1866: 1845: 1840: 1834: 1794: 1788: 1741: 1737: 1733: 1730: 1727: 1722: 1718: 1693: 1688: 1684: 1680: 1677: 1674: 1669: 1665: 1661: 1657: 1653: 1650: 1636:indeterminates 1621: 1617: 1613: 1610: 1607: 1602: 1598: 1586: 1585: 1574: 1571: 1568: 1563: 1559: 1555: 1552: 1547: 1544: 1541: 1537: 1533: 1530: 1527: 1522: 1519: 1516: 1512: 1506: 1502: 1498: 1493: 1489: 1461: 1458: 1456: 1453: 1389: 1383: 1358: 1352: 1319: 1313: 1273: 1267: 1235: 1229: 1204: 1201: 1186: 1182: 1152:quotient group 1116: 1113: 1109: 1105: 1102: 1099: 1096: 1060: 1057: 1053: 1049: 1046: 1043: 1040: 1017: 1014: 1011: 1008: 1005: 981: 977: 973: 956:establishes a 949: 946: 914: 911: 906: 902: 898: 893: 889: 866: 862: 835: 832: 829: 825: 802: 798: 786:roots of unity 771: 767: 744: 741: 738: 734: 704: 700: 679: 676: 671: 667: 644: 641: 638: 634: 630: 623: 619: 613: 609: 588: 585: 582: 579: 576: 573: 570: 567: 547: 542: 538: 534: 529: 526: 523: 519: 515: 510: 506: 483: 479: 475: 470: 466: 454: 453: 440: 436: 432: 429: 426: 421: 417: 413: 408: 404: 359: 356: 324: 321: 276: 273: 270: 267: 262: 258: 231:multiplication 217:, that is, an 172: 169: 144: 143: 132: 129: 126: 123: 120: 117: 112: 108: 71:indeterminates 32:Abel's theorem 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 4687: 4676: 4673: 4671: 4668: 4666: 4663: 4661: 4660:Galois theory 4658: 4657: 4655: 4642: 4636: 4632: 4628: 4624: 4620: 4616: 4610: 4607: 4600: 4599: 4591: 4588: 4585: 4581: 4574: 4571: 4567: 4563: 4559: 4555: 4551: 4549:1-4020-2186-0 4545: 4541: 4537: 4530: 4527: 4522: 4519:(in French), 4518: 4517: 4512: 4508: 4502: 4499: 4494: 4491:(in French), 4490: 4489: 4481: 4477: 4471: 4468: 4464: 4458: 4454: 4453:Basic Algebra 4450: 4444: 4441: 4437: 4433: 4429: 4423: 4419: 4415: 4408: 4406: 4402: 4398: 4392: 4388: 4384: 4383:Galois Theory 4380: 4374: 4371: 4366: 4362: 4358: 4354: 4353:Sylow, Ludwig 4347: 4343: 4337: 4334: 4330: 4326: 4322: 4318: 4314: 4310: 4306: 4302: 4298: 4294: 4293: 4285: 4283: 4279: 4274: 4270: 4264: 4261: 4256: 4252: 4248: 4242: 4239: 4235: 4231: 4227: 4225:0-262-66182-9 4221: 4217: 4214:, Cambridge: 4213: 4206: 4204: 4200: 4196: 4192: 4188: 4182: 4178: 4174: 4170: 4164: 4162: 4158: 4154: 4150: 4146: 4142: 4138: 4134: 4130: 4126: 4122: 4118: 4117: 4112: 4106: 4103: 4099: 4095: 4091: 4087: 4082: 4077: 4073: 4069: 4062: 4059: 4055: 4049: 4045: 4041: 4040:Galois Theory 4037: 4031: 4029: 4025: 4020: 4016: 4012: 4008: 4007:Sylow, Ludwig 4001: 3997: 3991: 3989: 3985: 3980: 3976: 3972: 3968: 3967:Sylow, Ludwig 3961: 3957: 3951: 3949: 3945: 3940: 3939: 3931: 3928: 3924: 3920: 3916: 3912: 3908: 3904: 3900: 3896: 3892: 3888: 3884: 3880: 3879: 3871: 3869: 3867: 3865: 3861: 3854: 3852: 3850: 3846: 3843:discovered a 3842: 3837: 3834: 3829: 3825: 3816: 3812: 3809:According to 3807: 3803: 3784: 3780: 3776: 3771: 3767: 3763: 3758: 3754: 3725: 3722: 3719: 3716: 3669: 3665: 3661: 3656: 3652: 3648: 3643: 3639: 3607: 3601: 3579: 3575: 3552: 3548: 3525: 3521: 3500: 3497: 3491: 3485: 3465: 3462: 3456: 3453: 3447: 3427: 3424: 3418: 3415: 3409: 3389: 3386: 3380: 3377: 3371: 3351: 3348: 3345: 3342: 3322: 3319: 3316: 3313: 3305: 3289: 3286: 3283: 3280: 3277: 3272: 3268: 3264: 3258: 3252: 3242: 3240: 3236: 3235:Paolo Ruffini 3228: 3224: 3223:Paolo Ruffini 3220: 3216: 3214: 3210: 3209: 3204: 3200: 3196: 3192: 3189:Around 1770, 3184: 3182: 3180: 3176: 3172: 3168: 3158: 3144: 3141: 3138: 3135: 3132: 3129: 3124: 3120: 3097: 3066: 3054: 3051: 3043: 3025: 3008: 2985: 2977: 2948: 2940: 2932: 2931:transposition 2929:, which is a 2914: 2910: 2884: 2857: 2849: 2819: 2816: 2811: 2807: 2803: 2798: 2794: 2784: 2781: 2778: 2775: 2770: 2766: 2740: 2732: 2710: 2669: 2666: 2663: 2660: 2655: 2651: 2637: 2623: 2620: 2617: 2614: 2611: 2608: 2603: 2599: 2591:The equation 2588: 2580: 2578: 2574: 2552: 2549: 2543: 2537: 2507: 2503: 2480: 2476: 2467: 2449: 2445: 2436: 2431: 2418: 2413: 2381: 2377: 2373: 2367: 2364: 2344: 2339: 2335: 2326: 2318: 2296: 2292: 2283: 2267: 2261: 2255: 2230: 2226: 2222: 2219: 2216: 2211: 2207: 2195: 2192: 2172: 2167: 2163: 2159: 2156: 2153: 2148: 2144: 2118: 2114: 2110: 2107: 2104: 2099: 2095: 2083: 2080: 2057: 2049: 2045: 2041: 2038: 2032: 2024: 2020: 2016: 2013: 2007: 2002: 1998: 1994: 1991: 1986: 1983: 1980: 1976: 1972: 1969: 1966: 1961: 1958: 1955: 1951: 1945: 1941: 1937: 1932: 1928: 1924: 1918: 1912: 1905: 1904: 1903: 1887: 1883: 1879: 1876: 1873: 1868: 1864: 1843: 1838: 1820: 1814: 1810: 1792: 1776: 1768: 1762: 1757: 1739: 1735: 1731: 1728: 1725: 1720: 1716: 1707: 1686: 1682: 1678: 1675: 1672: 1667: 1663: 1651: 1648: 1641: 1637: 1634:are distinct 1619: 1615: 1611: 1608: 1605: 1600: 1596: 1572: 1569: 1566: 1561: 1557: 1553: 1550: 1545: 1542: 1539: 1535: 1531: 1528: 1525: 1520: 1517: 1514: 1510: 1504: 1500: 1496: 1491: 1487: 1479: 1478: 1477: 1471: 1467: 1459: 1454: 1452: 1450: 1446: 1442: 1438: 1437:Galois theory 1434: 1430: 1426: 1420: 1414: 1410: 1405: 1387: 1356: 1339: 1335: 1317: 1298: 1293: 1289: 1271: 1255: 1252:has only the 1233: 1217: 1211: 1202: 1200: 1184: 1180: 1172: 1167: 1165: 1161: 1157: 1153: 1149: 1145: 1141: 1136: 1111: 1107: 1103: 1097: 1094: 1074: 1073:automorphisms 1055: 1051: 1047: 1041: 1038: 1031: 1015: 1012: 1009: 1006: 1003: 979: 975: 971: 963: 962:subextensions 959: 955: 947: 945: 943: 937: 935: 931: 925: 912: 904: 900: 891: 887: 864: 860: 851: 833: 830: 827: 823: 815:that extends 800: 796: 787: 769: 765: 742: 739: 736: 732: 723: 718: 702: 698: 677: 674: 669: 665: 642: 639: 636: 632: 628: 621: 617: 611: 607: 586: 583: 580: 577: 574: 571: 568: 565: 540: 536: 527: 524: 521: 517: 513: 508: 504: 481: 477: 473: 468: 464: 438: 434: 430: 427: 424: 419: 415: 411: 406: 402: 394: 393: 392: 389: 387: 380: 375: 373: 369: 365: 357: 355: 353: 349: 345: 341: 337: 332: 330: 329:Galois theory 322: 320: 318: 314: 313:Galois theory 310: 305: 302: 296: 294: 274: 271: 268: 265: 260: 256: 245: 243: 236: 232: 228: 224: 220: 216: 210: 208: 204: 200: 195: 193: 189: 188:cubic formula 185: 181: 177: 170: 168: 166: 162: 161:cubic formula 158: 153: 151: 150: 130: 127: 124: 121: 118: 115: 110: 106: 98: 97: 96: 94: 89: 85: 83: 79: 78:Paolo Ruffini 74: 72: 68: 64: 60: 56: 52: 48: 44: 40: 33: 19: 4618: 4609: 4597: 4590: 4573: 4535: 4529: 4520: 4514: 4501: 4492: 4486: 4470: 4452: 4443: 4413: 4382: 4379:Stewart, Ian 4373: 4360: 4336: 4296: 4290: 4272: 4263: 4254: 4241: 4211: 4172: 4120: 4114: 4105: 4071: 4067: 4061: 4039: 4036:Stewart, Ian 4014: 3974: 3937: 3930: 3882: 3876: 3838: 3823: 3808: 3804: 3513:, the roots 3243: 3232: 3226: 3206: 3195:permutations 3188: 3169:. This is a 3164: 2873:, the group 2638: 2590: 2572: 2432: 2282:permutations 2072: 1821: 1767:Galois group 1760: 1587: 1469: 1465: 1463: 1449:Galois group 1418: 1415: 1408: 1296: 1209: 1206: 1168: 1137: 1030:Galois group 960:between the 951: 938: 930:Galois group 926: 719: 455: 390: 376: 361: 344:Galois group 336:field theory 333: 326: 306: 297: 246: 211: 196: 174: 154: 147: 145: 87: 86: 75: 66: 63:coefficients 46: 42: 36: 4357:Lie, Sophus 4011:Lie, Sophus 3971:Lie, Sophus 3175:irreducible 3005:contains a 2755:factors as 1079:that leave 720:For having 496:such that 227:subtraction 59:degree five 53:to general 39:mathematics 4654:Categories 4566:1065.12001 4436:1333.12001 4234:1166.01010 4195:1333.12001 4153:0836.01015 3923:0471.01008 3855:References 2585:See also: 1439:is that a 1248:of degree 364:expression 219:expression 163:, and the 149:almost all 4495:: 417–433 4387:CRC Press 4344:(1881) , 4329:121442989 4216:MIT Press 4081:1211.3588 4044:CRC Press 3998:(1881) , 3958:(1881) , 3915:123447349 3839:In 1963, 3720:± 3454:− 3416:− 3378:− 3346:− 3287:− 3278:− 3136:− 3130:− 2667:− 2661:− 2615:− 2609:− 2368:⁡ 2220:… 2157:… 2108:… 2042:− 2033:⋯ 2017:− 1984:− 1970:⋯ 1959:− 1877:… 1729:… 1676:… 1609:… 1543:− 1529:⋯ 1518:− 1425:quadratic 1098:⁡ 1042:⁡ 1013:⊆ 1007:⊆ 831:− 740:− 640:− 629:∈ 578:… 525:− 474:∈ 431:⊆ 428:⋯ 425:⊆ 412:⊆ 266:− 184:antiquity 122:− 116:− 4617:(2014), 4509:(1845), 4478:(1846), 4359:(eds.), 4313:41133337 4271:(1799), 4013:(eds.), 3973:(eds.), 3899:41133596 3179:rational 2933:. Since 2725:. Since 1404:solvable 1402:are not 1154:that is 1144:solvable 932:that is 287:for any 235:division 223:addition 199:non-real 65:. Here, 4584:YouTube 4558:2110624 4523:: 57–65 4321:1554154 4253:(ed.), 4145:1336636 4137:2974763 4098:3230862 3907:0606270 3185:History 3044:. Thus 3007:5-cycle 2327:of the 2284:of the 1811:of the 1704:of the 1470:generic 1466:general 1433:quartic 1338:abelian 1294:). For 1160:abelian 1071:of the 1028:to the 171:Context 67:general 4637:  4564:  4556:  4546:  4459:  4434:  4424:  4393:  4327:  4319:  4311:  4232:  4222:  4193:  4183:  4151:  4143:  4135:  4096:  4050:  3921:  3913:  3905:  3897:  3567:, and 3478:, and 3229:, 1799 3213:thesis 3181:root. 2682:. Let 2575:> 4 1763:> 4 1588:where 1443:has a 1431:, and 1411:> 4 1334:simple 1299:> 4 1214:, the 1212:> 4 1156:cyclic 1148:normal 934:cyclic 388:root. 237:, and 159:, the 41:, the 4602:(PDF) 4483:(PDF) 4351:, in 4349:(PDF) 4325:S2CID 4309:JSTOR 4133:JSTOR 4076:arXiv 4005:, in 4003:(PDF) 3965:, in 3963:(PDF) 3911:S2CID 3895:JSTOR 2898:then 2323:is a 1769:over 1754:with 1640:field 1429:cubic 1290:(see 996:such 848:by a 599:with 379:field 323:Proof 4635:ISBN 4544:ISBN 4457:ISBN 4422:ISBN 4391:ISBN 4220:ISBN 4181:ISBN 4048:ISBN 3498:> 3463:< 3425:> 3387:< 2639:Let 2464:are 2433:The 2280:The 2185:and 2073:Let 1464:The 1406:for 1371:and 1207:For 952:The 784:-th 675:> 558:for 4627:doi 4582:on 4562:Zbl 4432:Zbl 4301:doi 4230:Zbl 4191:Zbl 4149:Zbl 4125:doi 4121:102 4086:doi 3919:Zbl 3887:doi 3594:of 2945:mod 2835:in 2737:mod 2643:be 2526:to 2365:Gal 1708:in 1468:or 1421:≤ 4 1332:is 1095:Gal 1087:of 1075:of 1039:Gal 879:as 57:of 37:In 4656:: 4633:, 4625:, 4560:, 4554:MR 4552:, 4542:, 4538:, 4513:, 4493:XI 4485:, 4430:, 4420:, 4404:^ 4389:, 4355:; 4323:, 4317:MR 4315:, 4307:, 4295:, 4281:^ 4228:, 4218:, 4202:^ 4189:, 4179:, 4160:^ 4147:, 4141:MR 4139:, 4131:, 4119:, 4094:MR 4092:, 4084:, 4072:17 4070:, 4046:, 4027:^ 4009:; 3987:^ 3969:; 3947:^ 3917:, 3909:, 3903:MR 3901:, 3893:, 3883:22 3881:, 3863:^ 3851:. 3717:10 3540:, 3440:, 3402:, 3343:10 3314:10 3290:20 3281:15 3225:, 2577:. 2315:. 1427:, 1135:. 944:. 936:. 678:1. 386:th 244:. 233:, 229:, 225:, 73:. 4629:: 4521:4 4303:: 4297:8 4127:: 4088:: 4078:: 3889:: 3820:4 3790:) 3785:3 3781:r 3777:, 3772:2 3768:r 3764:, 3759:1 3755:r 3751:( 3747:Q 3726:i 3723:5 3696:R 3675:) 3670:3 3666:r 3662:, 3657:2 3653:r 3649:, 3644:1 3640:r 3636:( 3632:Q 3611:) 3608:x 3605:( 3602:P 3580:3 3576:r 3553:2 3549:r 3526:1 3522:r 3501:0 3495:) 3492:5 3489:( 3486:P 3466:0 3460:) 3457:1 3451:( 3448:P 3428:0 3422:) 3419:2 3413:( 3410:P 3390:0 3384:) 3381:3 3375:( 3372:P 3352:i 3349:5 3323:i 3320:5 3317:+ 3284:x 3273:3 3269:x 3265:= 3262:) 3259:x 3256:( 3253:P 3145:0 3142:= 3139:1 3133:x 3125:5 3121:x 3098:5 3092:S 3067:5 3061:S 3055:= 3052:G 3026:5 3020:S 3003:G 2989:] 2986:x 2983:[ 2978:3 2973:F 2949:3 2941:q 2915:3 2911:g 2900:G 2885:g 2875:G 2861:] 2858:x 2855:[ 2850:2 2845:F 2823:) 2820:1 2817:+ 2812:2 2808:x 2804:+ 2799:3 2795:x 2791:( 2788:) 2785:1 2782:+ 2779:x 2776:+ 2771:2 2767:x 2763:( 2741:2 2733:q 2711:5 2705:S 2692:G 2688:q 2684:G 2670:1 2664:x 2656:5 2652:x 2641:q 2624:0 2621:= 2618:1 2612:x 2604:5 2600:x 2573:n 2568:n 2553:0 2550:= 2547:) 2544:x 2541:( 2538:P 2528:K 2524:F 2508:i 2504:b 2481:i 2477:a 2450:i 2446:b 2419:. 2414:n 2408:S 2385:) 2382:K 2378:/ 2374:H 2371:( 2345:, 2340:i 2336:x 2321:K 2313:H 2297:i 2293:x 2268:. 2265:) 2262:x 2259:( 2256:P 2236:) 2231:n 2227:b 2223:, 2217:, 2212:1 2208:b 2204:( 2200:Q 2196:= 2193:K 2173:, 2168:n 2164:x 2160:, 2154:, 2149:1 2145:x 2124:) 2119:n 2115:x 2111:, 2105:, 2100:1 2096:x 2092:( 2088:Q 2084:= 2081:H 2058:. 2055:) 2050:n 2046:x 2039:x 2036:( 2030:) 2025:1 2021:x 2014:x 2011:( 2008:= 2003:n 1999:b 1995:+ 1992:x 1987:1 1981:n 1977:b 1973:+ 1967:+ 1962:1 1956:n 1952:x 1946:1 1942:b 1938:+ 1933:n 1929:x 1925:= 1922:) 1919:x 1916:( 1913:P 1888:n 1884:x 1880:, 1874:, 1869:1 1865:x 1844:, 1839:n 1833:S 1817:F 1793:n 1787:S 1771:F 1761:n 1740:n 1736:a 1732:, 1726:, 1721:1 1717:a 1692:) 1687:n 1683:a 1679:, 1673:, 1668:1 1664:a 1660:( 1656:Q 1652:= 1649:F 1620:n 1616:a 1612:, 1606:, 1601:1 1597:a 1573:, 1570:0 1567:= 1562:n 1558:a 1554:+ 1551:x 1546:1 1540:n 1536:a 1532:+ 1526:+ 1521:1 1515:n 1511:x 1505:1 1501:a 1497:+ 1492:n 1488:x 1474:n 1419:n 1409:n 1388:n 1382:S 1357:n 1351:A 1318:n 1312:A 1297:n 1272:n 1266:A 1250:n 1234:n 1228:S 1210:n 1185:5 1181:S 1133:H 1129:F 1115:) 1112:E 1108:/ 1104:F 1101:( 1085:H 1081:K 1077:F 1059:) 1056:K 1052:/ 1048:F 1045:( 1016:F 1010:K 1004:E 994:K 980:E 976:/ 972:F 913:. 910:) 905:i 901:x 897:( 892:i 888:K 865:i 861:F 834:1 828:i 824:F 801:i 797:K 770:i 766:n 743:1 737:i 733:F 703:k 699:F 670:i 666:n 643:1 637:i 633:F 622:i 618:n 612:i 608:x 587:, 584:k 581:, 575:, 572:1 569:= 566:i 546:) 541:i 537:x 533:( 528:1 522:i 518:F 514:= 509:i 505:F 482:i 478:F 469:i 465:x 439:k 435:F 420:1 416:F 407:0 403:F 384:n 289:n 275:0 272:= 269:1 261:n 257:x 240:n 131:0 128:= 125:1 119:x 111:5 107:x 34:. 20:)

Index

Abel-Ruffini theorem
Abel's theorem
mathematics
solution in radicals
polynomial equations
degree five
coefficients
indeterminates
Paolo Ruffini
Niels Henrik Abel
Galois theory § A non-solvable quintic example
almost all
quadratic formula
cubic formula
quartic formula
Polynomial equations
quadratic formula
antiquity
cubic formula
quartic formula
non-real
fundamental theorem of algebra
Newton's method
solution in radicals
expression
addition
subtraction
multiplication
division
nth root extraction

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