>>395 こんなのがあった Brent Everitt, University of York, England
www-users.york.ac.uk/~bje1/galnotes.pdf Symmetries of Equations: An Introduction to Galois Theory Brent Everitt, version 1.12, December 19, 2007. Department of Mathematics, University of York, York YO10 5DD, England.
Contents 1. What is Galois Theory? .......3 （抜粋） "Evarist´e Galois started thinking about the deeper problem: why don’t these formulae exist? Thus Galois theory was originally motivated by the desire to understand, in a much more precise way than they hitherto had been, the solutions to polynomial equations. Galois’ idea was this: study the solutions by studying their “symmetries”. Nowadays, when we hear the word symmetry, we normally think of group theory rather than number theory. Actually, to reach his conclusions, Galois kind of invented group theory along the way. In studying the symmetries of the solutions to a polynomial, Galois theory establishes a link between these two areas of mathematics." （引用おわり）
