This text offers a clear, efficient exposition of Galois Theory with complete proofs and exercises. Topics include: cubic and quartic formulas; Fundamental Theory of Galois Theory; insolvability of the quintic; Galois's Great Theorem (solvability by radicals of a polynomial is equivalent to solvability of its Galois Group); and computation of Galois groups of cubics and quartics. There are appendices on group theory, ruler-compass constructions, and the early history of Galois Theory.

Zusammenfassung
It now begins with a short section on symmetry groups of polygons in the plane, for there is an analogy between polygons and their symmetry groups and polynomials and their Galois groups - an analogy which serves to help readers organise the various field theoretic definitions and constructions.

Inhalt
Symmetry.- Rings.- Domains and Fields.- Homomorphisms and Ideals.- Quotient Rings.- Polynomial Rings over Fields.- Prime Ideals and Maximal Ideals.- Irreducible Polynomials.- Classical Formulas.- Splitting Fields.- The Galois Group.- Roots of Unity.- Solvability by Radicals.- Independence of Characters.- Galois Extensions.- The Fundamental Theorem of Galois Theory.- Applications.- Galois's Great Theorem.- Discriminants.- Galois Groups of Quadratics, Cubics, and Quartics.- Epilogue.- Appendix A: Group Theory Dictionary.- Appendix B: Group Theory Used in the Text.- Appendix C: Ruler-Compass Constructions.- Appendix D: Old-fashioned Galois Theory.- References.