INTRODUCTION TO MODERN ALGEBRA AND MATRIX THEORY INTRODUCTION TO MODERN ALGEBRA AND MATRIX THEORY Second Edition O. SCHREIER E. SPERNER Translated by M D ARTIN AVIS AND M H ELVIN AUSNER DOVER PUBLICATIONS, INC. Mineola, New York Bibliographical Note This Dover edition, first published in 2011, is an unabridged republication of the work originally published in 1959 by Chelsea Publishing Company, New York. Library of Congress Cataloging-in-Publication Data Schreier, O. (Otto), 1901–1929. [Einführung in die analytische Geometeie und Algebra. English] Introduction to modern algebra and matrix / O. Schreier and E. Sperner. — Dover ed. p. cm. Originally published: 2nd ed. New York : Chelsea Pub., 1959. Summary: “This unique text provides students with a basic course in both calculus and analytic geometry. It promotes an intuitive approach to calculus and emphasizes algebraic concepts. Minimal prerequisites. Numerous exercises. 1951 edition”—Provided by publisher. Includes bibliographical references and index. ISBN-13: 978-0-486-48220-0 (pbk.) ISBN-10: 0-486-48220-0 (pbk.) 1. Geometry, Analytic. 2. Algebra. I. Sperner, E. (Emanuel), 1905- II. Title. QA551.S433 2011 516.3—dc22 2011000043 Manufactured in the United States by Courier Corporation 48220001 www.doverpublications.com EDITOR’S PREFACE Schreier and Sperner’s justly famous Einführung in die Algebra und Analytische Geometrie was originally published in two volumes. Both of these volumes (with the omission of a final chapter on projective geometry) are here presented in a one-volume English translation, under the title Introduction to Modern Algebra and Matrix Theory. It may be noted that Chapter V of the present translation (Volume II, Chapter II of the original) incorporates the material of the authors’ book Lectures on Matrices (Vorlesungen über Matrizen). F. S. A. G. TRANSLATOR’S PREFACE We wish to thank Dr. F. Steinhardt for his very valuable help in the preparation of the present translation. Thanks are due, also, to Miss Zelma Ann McCormick. MARTIN DAVIS MELVIN HAUSNER FROM THE PREFACE TO VOLUME I OF THE GERMAN EDITION Otto Schreier had planned, a few years ago, to have his lectures on Analytic Geometry and Algebra published in book form. Death overtook him in Hamburg on June 2, 1929, before he had really begun to carry out his plan. The task of doing this fell on me, his pupil. I had at my disposal some sets of lecture notes taken at Schreier’s courses, as well as a detailed (if not quite complete) syllabus of his course drawn up at one time by Otto Schreier himself. Since then, I have also given the course myself, in Hamburg, gaining experience in the process. In writing the book I have followed Schreier’s presentation as closely as possible, so that the textbook might retain the characteristics impressed on the subject matter in Otto Schreier’s treatment. In particular, as regards choice and arrangement of material, I have followed Schreier’s outline faithfully, except for a few changes of minor importance. This textbook is motivated by the idea of offering the student, in two basic courses on Calculus and Analytic Geometry, all that he needs for a profitable continuation of his studies adapted to modern requirements. It is evident that this implies a stronger emphasis than has been customary on algebra, in line with the recent developments in that subject. The prerequisites for reading this book are few indeed. For the early parts, a knowledge of the real number system —such as is acquired in the first few lectures of almost any calculus course—is sufficient. The later chapters make use of some few theorems on continuity of real functions and on sequences of real numbers. These also will be familiar to the student from the calculus. In some sections which give intuitive interpretations of the subject matter, use is made of some well-known theorems of elementary geometry, whose derivation on an axiomatic basis would of course be beyond the scope of this text. What the book contains may be seen in outline by a glance at the table of contents. The student is urged not to neglect the exercises at the end of each section; among them will be found many an important addition to the material presented in the text. To Messrs. E. Artin and W. Blaschke in Hamburg I wish to extend my most cordial thanks for their manifold help. I also wish to express my gratitude for reading the proofs, to Miss A. Voss (Hamburg) and to Messrs. R. Brauer (Koenigsberg), G. Feigl (Berlin), K. Henke (Hamburg), and E. Schubarth (Basel). EMANUEL SPERNER FROM THE PREFACE TO VOLUME II OF THE GERMAN EDITION The second volume of Einführung in die Analytische Geometrie und Algebra… is divided into three chapters, the first two of which [Chapters IV and V of the present translation] deal with algebraic topics, while the last, and longest, [to be published as a separate volume.—Ed.] is an analytic treatment of (n-dimensional) projective geometry. The authors’ earlier monograph, Vorlesungen über Matrizen (Hamburger Einzelschriften, Vol. 12) has been incorporated into [Chapter V of] the present book, with a few re-arrangements and omissions in order to achieve a more organic whole. • • • To Mr. W. Blaschke (Hamburg) I owe a debt of gratitude for his continuous interest and help. I also wish to thank Messrs. O. Haupt (Erlangen) and K. Henke (Hamburg) for many valuable hints and suggestions. In preparing the manuscript, my wife has given me untiring assistance. For reading the proofs I am indebted to Mr. H. Bueckner (Koenigsberg), in addition to those named above. Koenigsberg, October 1935. EMANUEL SPERNER TABLE OF CONTENTS EDITOR’S PREFACE TRANSLATORS’ PREFACE AUTHORS’ PREFACE C I HAPTER AFFINE SPACE; LINEAR EQUATIONS § 1. n-dimensional Affine Space § 2. Vectors § 3. The Concept of Linear Dependence § 4. Vector Spaces in R n § 5. Linear Spaces § 6. Linear Equations Homogeneous Linear Equations Non-homogeneous Linear Equations Geometric Applications C II HAPTER EUCLIDEAN SPACE; THEORY OF DETERMINANTS § 7. Euclidean Length Appendix to § 7: Calculating with the Summation Sign § 8. Volumes and Determinants Fundamental Properties of Determinants