文档介绍：To Alina and to Our Mothers
Titu Andreescu
Razvan˘ Gelca
Mathematical
Olympiad
Challenges
SECOND EDITION
Foreword by Mark Saul
Birkhäuser
Boston • Basel • Berlin
Titu Andreescu Răzvan Gelca
University of Texas at Dallas Texas Tech University
School of Natural Sciences Department of Mathematics
and Mathematics and Statistics
Richardson, TX 75080 Lubbock, TX 79409
USA USA
titu.******@ rgelca@
ISBN: 978-0-8176-4528-1 e-ISBN: 978-0-8176-4611-0
DOI: -0-8176-4611-0
Mathematics Subject Classification (2000): 00A05, 00A07, 05-XX, 11-XX, 51XX
© Birkhäuser Boston, a part of Springer Science+Business Media, LLC, Second Edition 2009
© Birkhäuser Boston, First Edition 2000
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Printed on acid-free paper
Contents
Foreword xi
Preface to the Second Edition xiii
Preface to the First Edition xv
IProblems 1
1 Geometry and Trigonometry 3
................... 4
.......................... 6
............................. 10
Dissections of Polygonal Surfaces . . . ................ 15
Regular Polygons . ........................... 20
............. 25