Numeros Complexos De a a Z.Pdf

Total Page:16

File Type:pdf, Size:1020Kb

Numeros Complexos De a a Z.Pdf About the Authors Titu Andreescu received his BA, MS, and PhD from the West University of Timisoara, Romania. The topic of his doctoral dissertation was “Research on Diophantine Analysis and Applications.” Professor Andreescu currently teaches at the University of Texas at Dallas. Titu is past chairman of the USA Mathematical Olympiad, served as director of the MAA American Mathemat- ics Competitions (1998–2003), coach of the USA International Mathematical Olympiad Team (IMO) for 10 years (1993–2002), Director of the Mathemat- ical Olympiad Summer Program (1995–2002) and leader of the USA IMO Team (1995–2002). In 2002 Titu was elected member of the IMO Advisory Board, the governing body of the world’s most prestigious mathematics com- petition. Titu received the Edyth May Sliffe Award for Distinguished High School Mathematics Teaching from the MAA in 1994 and a “Certificate of Appreciation” from the president of the MAA in 1995 for his outstanding service as coach of the Mathematical Olympiad Summer Program in prepar- ing the US team for its perfect performance in Hong Kong at the 1994 IMO. Titu’s contributions to numerous textbooks and problem books are recognized worldwide. Dorin Andrica received his PhD in 1992 from “Babes¸-Bolyai” University in Cluj-Napoca, Romania, with a thesis on critical points and applications to the geometry of differentiable submanifolds. Professor Andrica has been chair- man of the Department of Geometry at “Babes¸-Bolyai” since 1995. Dorin has written and contributed to numerous mathematics textbooks, problem books, articles and scientific papers at various levels. Dorin is an invited lecturer at university conferences around the world—Austria, Bulgaria, Czech Republic, Egypt, France, Germany, Greece, the Netherlands, Serbia, Turkey, and USA. He is a member of the Romanian Committee for the Mathematics Olympiad and member of editorial boards of several international journals. Dorin has been a regular faculty member at the Canada–USA Mathcamps since 2001. Titu Andreescu Dorin Andrica Complex Numbers fromAto...Z Birkhauser¨ Boston • Basel • Berlin Dorin Andrica Titu Andreescu “Babes¸-Bolyai” University University of Texas at Dallas Faculty of Mathematics School of Natural Sciences and Mathematics 3400 Cluj-Napoca Richardson, TX 75083 Romania U.S.A. Cover design by Mary Burgess. Mathematics Subject Classification (2000): 00A05, 00A07, 30-99, 30A99, 97U40 Library of Congress Cataloging-in-Publication Data Andreescu, Titu, 1956- Complex numbers from A to–Z / Titu Andreescu, Dorin Andrica. p. cm. “Partly based on a Romanian version . preserving the title. and about 35% of the text”–Pref. Includes bibliographical references and index. ISBN 0-8176-4326-5 (acid-free paper) 1. Numbers, Complex. I. Andrica, D. (Dorin) II. Andrica, D. (Dorin) Numere complexe QA255.A558 2004 512.7’88–dc22 2004051907 ISBN-10 0-8176-4326-5 eISBN 0-8176-4449-0 Printed on acid-free paper. ISBN-13 978-0-8176-4326-3 c 2006 Birkhauser¨ Boston Complex Numbers from A to...Zis a greatly expanded and substantially enhanced version of the Romanian edition, Numere complexe de la A la...Z, S.C. Editura Millenium S.R. L., Alba Iulia, Romania, 2001 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Birkhauser¨ Boston, c/o Springer Science+Business Media Inc., 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly anal- ysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed in the United States of America. (TXQ/MP) 987654321 www.birkhauser.com The shortest path between two truths in the real domain passes through the complex domain. Jacques Hadamard About the Authors Titu Andreescu received his BA, MS, and PhD from the West University of Timisoara, Romania. The topic of his doctoral dissertation was “Research on Diophantine Analysis and Applications.” Professor Andreescu currently teaches at the University of Texas at Dallas. Titu is past chairman of the USA Mathematical Olympiad, served as director of the MAA American Mathemat- ics Competitions (1998–2003), coach of the USA International Mathematical Olympiad Team (IMO) for 10 years (1993–2002), Director of the Mathemat- ical Olympiad Summer Program (1995–2002) and leader of the USA IMO Team (1995–2002). In 2002 Titu was elected member of the IMO Advisory Board, the governing body of the world’s most prestigious mathematics com- petition. Titu received the Edyth May Sliffe Award for Distinguished High School Mathematics Teaching from the MAA in 1994 and a “Certificate of Appreciation” from the president of the MAA in 1995 for his outstanding service as coach of the Mathematical Olympiad Summer Program in prepar- ing the US team for its perfect performance in Hong Kong at the 1994 IMO. Titu’s contributions to numerous textbooks and problem books are recognized worldwide. Dorin Andrica received his PhD in 1992 from “Babes¸-Bolyai” University in Cluj-Napoca, Romania, with a thesis on critical points and applications to the geometry of differentiable submanifolds. Professor Andrica has been chair- man of the Department of Geometry at “Babes¸-Bolyai” since 1995. Dorin has written and contributed to numerous mathematics textbooks, problem books, articles and scientific papers at various levels. Dorin is an invited lecturer at university conferences around the world—Austria, Bulgaria, Czech Republic, Egypt, France, Germany, Greece, the Netherlands, Serbia, Turkey, and USA. He is a member of the Romanian Committee for the Mathematics Olympiad and member of editorial boards of several international journals. Dorin has been a regular faculty member at the Canada–USA Mathcamps since 2001. Titu Andreescu Dorin Andrica Complex Numbers fromAto...Z Birkhauser¨ Boston • Basel • Berlin Dorin Andrica Titu Andreescu “Babes¸-Bolyai” University University of Texas at Dallas Faculty of Mathematics School of Natural Sciences and Mathematics 3400 Cluj-Napoca Richardson, TX 75083 Romania U.S.A. Cover design by Mary Burgess. Mathematics Subject Classification (2000): 00A05, 00A07, 30-99, 30A99, 97U40 Library of Congress Cataloging-in-Publication Data Andreescu, Titu, 1956- Complex numbers from A to–Z / Titu Andreescu, Dorin Andrica. p. cm. “Partly based on a Romanian version . preserving the title. and about 35% of the text”–Pref. Includes bibliographical references and index. ISBN 0-8176-4326-5 (acid-free paper) 1. Numbers, Complex. I. Andrica, D. (Dorin) II. Andrica, D. (Dorin) Numere complexe QA255.A558 2004 512.7’88–dc22 2004051907 ISBN-10 0-8176-4326-5 eISBN 0-8176-4449-0 Printed on acid-free paper. ISBN-13 978-0-8176-4326-3 c 2006 Birkhauser¨ Boston Complex Numbers from A to...Zis a greatly expanded and substantially enhanced version of the Romanian edition, Numere complexe de la A la...Z, S.C. Editura Millenium S.R. L., Alba Iulia, Romania, 2001 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Birkhauser¨ Boston, c/o Springer Science+Business Media Inc., 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly anal- ysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed in the United States of America. (TXQ/MP) 987654321 www.birkhauser.com Contents Preface ix Notation xiii 1 Complex Numbers in Algebraic Form 1 1.1 Algebraic Representation of Complex Numbers ............ 1 1.1.1 Definition of complex numbers . ............... 1 1.1.2 Properties concerning addition . ............... 2 1.1.3 Properties concerning multiplication .............. 3 1.1.4 Complex numbers in algebraic form .............. 5 1.1.5 Powers of the number i ..................... 7 1.1.6 Conjugate of a complex number . ............... 8 1.1.7 Modulus of a complex number . ............... 9 1.1.8 Solving quadratic equations ................... 15 1.1.9 Problems ............................ 18 1.2 Geometric Interpretation of the Algebraic Operations . ....... 21 1.2.1 Geometric interpretation of a complex number . ....... 21 1.2.2 Geometric interpretation of the modulus ............ 23 1.2.3 Geometric interpretation of the algebraic operations ...... 24 1.2.4 Problems ............................ 27 vi Contents 2 Complex Numbers in Trigonometric Form 29 2.1 Polar Representation of Complex Numbers .............. 29 2.1.1 Polar coordinates in the plane . ............... 29 2.1.2 Polar representation of a complex number ........... 31 2.1.3 Operations with complex numbers in polar representation . 36 2.1.4 Geometric interpretation of multiplication ........... 39 2.1.5 Problems ............................ 39 2.2 The nth Roots of Unity . ....................... 41 2.2.1 Defining the nth roots of a complex number . ....... 41 2.2.2 The nth roots of unity ...................... 43 2.2.3 Binomial equations ....................... 51 2.2.4 Problems ............................ 52 3 Complex Numbers and Geometry 53 3.1 Some Simple Geometric Notions and Properties ............ 53 3.1.1 The distance between two points . ............... 53 3.1.2 Segments, rays and lines .................... 54 3.1.3 Dividing a segment into a given ratio .............. 57 3.1.4 Measure of an angle ....................... 58 3.1.5 Angle between two lines .................... 61 3.1.6 Rotation of a point ......................
Recommended publications
  • Angle Chasing
    Angle Chasing Ray Li June 12, 2017 1 Facts you should know 1. Let ABC be a triangle and extend BC past C to D: Show that \ACD = \BAC + \ABC: 2. Let ABC be a triangle with \C = 90: Show that the circumcenter is the midpoint of AB: 3. Let ABC be a triangle with orthocenter H and feet of the altitudes D; E; F . Prove that H is the incenter of 4DEF . 4. Let ABC be a triangle with orthocenter H and feet of the altitudes D; E; F . Prove (i) that A; E; F; H lie on a circle diameter AH and (ii) that B; E; F; C lie on a circle with diameter BC. 5. Let ABC be a triangle with circumcenter O and orthocenter H: Show that \BAH = \CAO: 6. Let ABC be a triangle with circumcenter O and orthocenter H and let AH and AO meet the circumcircle at D and E, respectively. Show (i) that H and D are symmetric with respect to BC; and (ii) that H and E are symmetric with respect to the midpoint BC: 7. Let ABC be a triangle with altitudes AD; BE; and CF: Let M be the midpoint of side BC. Show that ME and MF are tangent to the circumcircle of AEF: 8. Let ABC be a triangle with incenter I, A-excenter Ia, and D the midpoint of arc BC not containing A on the circumcircle. Show that DI = DIa = DB = DC: 9. Let ABC be a triangle with incenter I and D the midpoint of arc BC not containing A on the circumcircle.
    [Show full text]
  • Cyclic Quadrilaterals — the Big Picture Yufei Zhao [email protected]
    Winter Camp 2009 Cyclic Quadrilaterals Yufei Zhao Cyclic Quadrilaterals | The Big Picture Yufei Zhao [email protected] An important skill of an olympiad geometer is being able to recognize known configurations. Indeed, many geometry problems are built on a few common themes. In this lecture, we will explore one such configuration. 1 What Do These Problems Have in Common? 1. (IMO 1985) A circle with center O passes through the vertices A and C of triangle ABC and intersects segments AB and BC again at distinct points K and N, respectively. The circumcircles of triangles ABC and KBN intersects at exactly two distinct points B and M. ◦ Prove that \OMB = 90 . B M N K O A C 2. (Russia 1995; Romanian TST 1996; Iran 1997) Consider a circle with diameter AB and center O, and let C and D be two points on this circle. The line CD meets the line AB at a point M satisfying MB < MA and MD < MC. Let K be the point of intersection (different from ◦ O) of the circumcircles of triangles AOC and DOB. Show that \MKO = 90 . C D K M A O B 3. (USA TST 2007) Triangle ABC is inscribed in circle !. The tangent lines to ! at B and C meet at T . Point S lies on ray BC such that AS ? AT . Points B1 and C1 lies on ray ST (with C1 in between B1 and S) such that B1T = BT = C1T . Prove that triangles ABC and AB1C1 are similar to each other. 1 Winter Camp 2009 Cyclic Quadrilaterals Yufei Zhao A B S C C1 B1 T Although these geometric configurations may seem very different at first sight, they are actually very related.
    [Show full text]
  • The Role of Euclidean Geometry in High School
    JOURNAL OF MATHEMATICAL BEHAVIOR 15, 221-237 (1996) The Role of Euclidean Geometry in High School HUNG-HSI Wu University of California When I was a high school student long ago, the need to study Euclidean geome- try was taken for granted. In fact, the novelty of learning to prove something was so overwhelming to me and some of my friends that, years later, we would look back at Euclidean geometry as the high point of our mathematics education. In recent years, the value of Euclid has depreciated considerably. A vigorous debate is now going on about how much, if any, of his work is still relevant. In this article, I would like to give my perspective on this subject, and in so doing, I will be taking a philosophical tour, so to speak, of a small portion of mathematics. This may not be so surprising because after all, in life as in mathematics, one does need a little philosophy for guidance from time to time. The bone of contention in the geometry curriculum is of course how many of the traditional “two-column proofs” should be retained. Let me first briefly indicate the range of available options in this regard: 1. A traditional text in use in a local high school in Berkeley not too long ago begins on page 1 with the undefined terms of the axioms, and formal proofs start on page 22. There is no motivation or explanation of the whys and hows of an axiomatic system. 2. A recently published text does experimental geometry (i.e., “hands-on ge- ometry” with no proofs) all the way until the last 130 pages of its 700 pages of exposition.
    [Show full text]
  • Prove It Classroom
    How to Prove it ClassRoom SHAILESH SHIRALI Euler’s formula for the area of a pedal triangle Given a triangle ABC and a point P in the plane of ABC In this episode of “How (note that P does not have to lie within the triangle), the To Prove It”, we prove pedal triangle of P with respect to ABC is the triangle △ a beautiful and striking whose vertices are the feet of the perpendiculars drawn from formula first found by P to the sides of ABC. See Figure 1. The pedal triangle relates Leonhard Euler; it gives the area of the pedal triangle in a natural way to the parent triangle, and we may wonder of a point with reference whether there is a convenient formula giving the area of the to another triangle. pedal triangle in terms of the parameters of the parent triangle. The great 18th-century mathematician Euler found just such a formula (given in Box 1). It is a compact and pleasing result, and it expresses the area of the pedal triangle in terms of the radius R of the circumcircle of ABC and the △ distance between P and the centre O of the circumcircle. A O: circumcentre of ABC E △ P: arbitrary point Area ( DEF) 1 OP2 F △ = 1 P Area ( ABC) 4 − R2 O △ ( ) B D C Figure 1. Euler's formula for the area of the pedal triangle of an arbitrary point Keywords: Circle theorem, pedal triangle, power of a point, Euler, sine rule, extended sine rule, Wallace-Simson theorem Azim Premji University At Right Angles, July 2018 95 1 A E F P O B D C Figure 2.
    [Show full text]
  • The Secrets of Triangles: a Mathematical Journey
    2 3 Published 2012 by Prometheus Books The Secrets of Triangles: A Mathematical Journey. Copyright © 2012 by Alfred S. Posamentier and Ingmar Lehmann. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, digital, electronic, mechanical, photocopying, recording, or otherwise, or conveyed via the Internet or a website without prior written permission of the publisher, except in the case of brief quotations embodied in critical articles and reviews. Cover image © Media Bakery/Glenn Mitsui Jacket design by Jacqueline Nasso Cooke Inquiries should be addressed to Prometheus Books 59 John Glenn Drive Amherst, New York 14228–2119 OICE: 716–691–0133 FAX: 716–691–0137 WWW.PROMETHE SBOOKS.COM 16 15 14 13 12 5 4 3 2 1 Library of Congress Cataloging-in-Publication Data Posamentier, Alfred S. The secrets of triangles : a mathematical journey / by Alfred S. Posamentier and Ingmar Lehmann. p. cm. Includes bibliographical references and index. ISBN 978–1–61614–587–3 (cloth : alk. paper) ISBN 978–1–61614–588–0 (ebook) 1. Trigonometry. 2. Triangle. I. Lehmann, Ingmar. II. Title. QA531.P67 2012 516'.154—dc23 2012013635 4 Printed in the nited States of America on acid-free paper 5 6 Acknowledgments Preface 1. Introduction to the Triangle 2. Concurrencies of a Triangle 3. Noteworthy Points in a Triangle 4. Concurrent Circles of a Triangle 5. Special Lines of a Triangle 6. seful Triangle Theorems 7. Areas of and within Triangles 8. Triangle Constructions 9. Inequalities in a Triangle 10. Triangles and Fractals Appendix Notes References Index 7 The authors wish to extend sincere thanks for proofreading and useful suggestions to Dr.
    [Show full text]
  • Topics in Elementary Geometry
    Topics in Elementary Geometry Second Edition O. Bottema (deceased) Topics in Elementary Geometry Second Edition With a Foreword by Robin Hartshorne Translated from the Dutch by Reinie Erne´ 123 O. Bottema Translator: (deceased) Reinie Ern´e Leiden, The Netherlands [email protected] ISBN: 978-0-387-78130-3 e-ISBN: 978-0-387-78131-0 DOI: 10.1007/978-0-387-78131-0 Library of Congress Control Number: 2008931335 Mathematics Subject Classification (2000): 51-xx This current edition is a translation of the Second Dutch Edition of, Hoofdstukken uit de Elementaire Meetkunde, published by Epsilon-Uitgaven, 1987. c 2008 Springer Science+Business Media, LLC All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connec- tion with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed on acid-free paper 987654321 springer.com At school I was good in mathematics; now I discovered that I found the so-called higher mathematics – differential and integral calculus – easier than the complicated (but elementary) plane geometry.
    [Show full text]
  • Complements to Classic Topics of Circles Geometry
    Ion Patrascu | Florentin Smarandache Complements to Classic Topics of Circles Geometry Pons Editions Brussels | 2016 Complements to Classic Topics of Circles Geometry Ion Patrascu | Florentin Smarandache Complements to Classic Topics of Circles Geometry 1 Ion Patrascu, Florentin Smarandache In the memory of the first author's father Mihail Patrascu and the second author's mother Maria (Marioara) Smarandache, recently passed to eternity... 2 Complements to Classic Topics of Circles Geometry Ion Patrascu | Florentin Smarandache Complements to Classic Topics of Circles Geometry Pons Editions Brussels | 2016 3 Ion Patrascu, Florentin Smarandache © 2016 Ion Patrascu & Florentin Smarandache All rights reserved. This book is protected by copyright. No part of this book may be reproduced in any form or by any means, including photocopying or using any information storage and retrieval system without written permission from the copyright owners. ISBN 978-1-59973-465-1 4 Complements to Classic Topics of Circles Geometry Contents Introduction ....................................................... 15 Lemoine’s Circles ............................................... 17 1st Theorem. ........................................................... 17 Proof. ................................................................. 17 2nd Theorem. ......................................................... 19 Proof. ................................................................ 19 Remark. ............................................................ 21 References.
    [Show full text]
  • Complements to Classic Topics of Circles Geometry
    University of New Mexico UNM Digital Repository Mathematics and Statistics Faculty and Staff Publications Academic Department Resources 2016 Complements to Classic Topics of Circles Geometry Florentin Smarandache University of New Mexico, [email protected] Ion Patrascu Follow this and additional works at: https://digitalrepository.unm.edu/math_fsp Part of the Algebra Commons, Algebraic Geometry Commons, Applied Mathematics Commons, Geometry and Topology Commons, and the Other Mathematics Commons Recommended Citation Smarandache, Florentin and Ion Patrascu. "Complements to Classic Topics of Circles Geometry." (2016). https://digitalrepository.unm.edu/math_fsp/264 This Book is brought to you for free and open access by the Academic Department Resources at UNM Digital Repository. It has been accepted for inclusion in Mathematics and Statistics Faculty and Staff Publications by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected], [email protected], [email protected]. Ion Patrascu | Florentin Smarandache Complements to Classic Topics of Circles Geometry Pons Editions Brussels | 2016 Complements to Classic Topics of Circles Geometry Ion Patrascu | Florentin Smarandache Complements to Classic Topics of Circles Geometry 1 Ion Patrascu, Florentin Smarandache In the memory of the first author's father Mihail Patrascu and the second author's mother Maria (Marioara) Smarandache, recently passed to eternity... 2 Complements to Classic Topics of Circles Geometry Ion Patrascu | Florentin Smarandache Complements to Classic Topics of Circles Geometry Pons Editions Brussels | 2016 3 Ion Patrascu, Florentin Smarandache © 2016 Ion Patrascu & Florentin Smarandache All rights reserved. This book is protected by copyright. No part of this book may be reproduced in any form or by any means, including photocopying or using any information storage and retrieval system without written permission from the copyright owners.
    [Show full text]
  • Volume One: Geometry Without Multiplication
    Geometry–Do Volume One: Geometry without Multiplication by Victor Aguilar, author of Axiomatic Theory of Economics Chapters Postulates White Belt Foundations 1. Two points fully define the segment between them. Yellow Belt Congruence 2. By extending it, a segment fully defines a line. Orange Belt Parallelograms 3. Three noncollinear points fully define a triangle. Green Belt Triangle Construction 4. The center and the radius fully define a circle. Red Belt Triangles, Advanced 5. All right angles are equal; equivalently, all straight Blue Belt Quadrature Theory angles are equal. Cho–Dan Harmonic Division 6. A line and a point not on it fully define the parallel Yi–Dan Circle Inversion through that point. This book was NOT funded by the Bill and Melinda Gates Foundation. A journey of discovery? A death march? It’s the same thing! Copyright ©2020 This PDF file, which consists only of the foundational pages and the index, is the ONLY authorized free PDF file for Geometry–Do. Do not accept PDF files that do not have the copyright notice. www.researchgate.net/publication/291333791_Volume_One_Geometry_without_Multiplication Volume One, white through red belt, is available as a bound paperback, as is an abridgement consisting of white, yellow and early orange belt. Free review copies are available to mathematicians. Teachers can purchase individual copies from book sellers or contact me directly for quantity discounts, but I do not need the reviews of people with education degrees, so no free review copies are available to them. A math degree is a degree granted by a university mathematics department; people with an education degree (granted by a university education department) should not call it a math degree; doing so will not get them a free review copy.
    [Show full text]
  • Volume 7 2007
    FORUM GEOMETRICORUM A Journal on Classical Euclidean Geometry and Related Areas published by Department of Mathematical Sciences Florida Atlantic University b b b FORUM GEOM Volume 7 2007 http://forumgeom.fau.edu ISSN 1534-1178 Editorial Board Advisors: John H. Conway Princeton, New Jersey, USA Julio Gonzalez Cabillon Montevideo, Uruguay Richard Guy Calgary, Alberta, Canada Clark Kimberling Evansville, Indiana, USA Kee Yuen Lam Vancouver, British Columbia, Canada Tsit Yuen Lam Berkeley, California, USA Fred Richman Boca Raton, Florida, USA Editor-in-chief: Paul Yiu Boca Raton, Florida, USA Editors: Clayton Dodge Orono, Maine, USA Roland Eddy St. John’s, Newfoundland, Canada Jean-Pierre Ehrmann Paris, France Chris Fisher Regina, Saskatchewan, Canada Rudolf Fritsch Munich, Germany Bernard Gibert St Etiene, France Antreas P. Hatzipolakis Athens, Greece Michael Lambrou Crete, Greece Floor van Lamoen Goes, Netherlands Fred Pui Fai Leung Singapore, Singapore Daniel B. Shapiro Columbus, Ohio, USA Steve Sigur Atlanta, Georgia, USA Man Keung Siu Hong Kong, China Peter Woo La Mirada, California, USA Technical Editors: Yuandan Lin Boca Raton, Florida, USA Aaron Meyerowitz Boca Raton, Florida, USA Xiao-Dong Zhang Boca Raton, Florida, USA Consultants: Frederick Hoffman Boca Raton, Floirda, USA Stephen Locke Boca Raton, Florida, USA Heinrich Niederhausen Boca Raton, Florida, USA Table of Contents Joseph Stern, Euler’s triangle determination problem, 1 Christopher Bradley, David Monk, and Geoff Smith, On a porism associated with the Euler and Droz-Farny lines, 11 Yu-Dong Wu and Zhi-Hua Zhang, The edge-tangent sphere of a circumscriptible tetrahedron, 19 Melissa Baker and Robert Powers, A stronger triangle inequality for neutral geometry, 25 Jingcheng Tong and Sidney Kung, A simple construction of the golden ratio, 31 Tom M.
    [Show full text]
  • Proceedings of the Indiana Academy of Science
    101 Note on "Note on Smith's Definition of Multiplication." By A. L. Baker. The rule should be: To multiply one quantity by another, perform upon the multiplicand the series of operations which was performed upon unity to produce the multiplier. This does not mean, perform upon the multiplicand the series of suc- cessive operations which was performed upon unity and upon the suc- cessive results. Thus, to multiply b by Va: If we attempt to consider Va as derived by taking unity a times and then extracting the square root of the result, we violate the rule. To get Va by performing operations upon unity, we must (e. g., a=2) talie unity 1 time, .4 times, .01 times, .004 times, etc., and add the results. Doing this to b, we get the correct result, viz., V2 b= 1.414... b. The rule is thus universal, applying to all multipliers, complex, qua- ternion and irrational. The Geometry of Siwson's Line. By C. E. Smith, Indiana University. 1. If from any point in the circumference of the circumcircle to a A ABC J.S to the sides of the /\ be drawn, their feet, Pj, Pj, and P3, lie in a straight line. This is known as Simson's Line. (a) First proof that Pj, Pj, and P3 lie in a straight line. Since Z s PP3 B and PPi B (Fig. 1.) are both right Z s, P, P3, Pj and B jire concyclic. Liliewise P, Pj, A, and Pg are concyclic. Now Z PP3 Pi -f Z PBPi = 180°.
    [Show full text]
  • The Mathematical Gazette Index for 1894 to 1908
    The Mathematical Gazette Index for 1894 to 1908 AUTHOR TITLE PAGE Issue Category C.W.Adams Stability of cube floating in liquid p. 388 Dec 1908 MNote 285 V.Ramaswami Aiyar Extension of Euclid I.47 to n-sided regular polygons p. 109 June 1897 MNote 41 V.Ramaswami Aiyar On a fundamental theorem in inversion p. 88 Oct 1904 MNote 153 V.Ramaswami Aiyar On a fundamental theorem in inversion p. 275 Jan 1906 MNote 183 V.Ramaswami Aiyar Note on a point in the demonstration of the binomial theorem p. 276 Jan 1906 MNote 185 V.Ramaswami Aiyar Note on the power inequality p. 321 May 1906 MNote 192 V.Ramaswami Aiyar On the exponential inequalities and the exponential function p. 8 Jan 1907 Article V.Ramaswami Aiyar The A, B, C of the higher analysis p. 79 May 1907 Article V.Ramaswami Aiyar On Stolz and Gmeiner’s proof of the sine and cosine series p. 282 June 1908 MNote 259 V.Ramaswami Aiyar A geometrical proof of Feuerbach’s theorem p. 310 July 1908 MNote 264 A.O.Allen On the adjustment of Kater’s pendulum p. 307 May 1906 Article A.O.Allen Notes on the theory of the reversible pendulum p. 394 Dec 1906 Article Anonymous Proof of a well-known theorem in geometry p. 64 Oct 1896 MNote 30 Anonymous Notes connected with the analytical geometry of the straight line p. 158 Feb 1898 MNote 49 Anonymous Method of reducing central conics p. 225 Dec 1902 MNote 110B (note) Anonymous On a fundamental theorem in inversion p.
    [Show full text]