The Teaching of Geometry 40

Total Page:16

File Type:pdf, Size:1020Kb

The Teaching of Geometry 40 THE TEACHING OF GEOMETRY BY DAVID EUGENE SMITH GINN AND COMPANY BOSTON " NEW YORK " CHICAGO " LONDON ' ' ' fli''/,T'/. / HARVARD COLLEGE LIBRARY 3y txcfcangefrom l^5!^"LINCOL.VEGt LIBRARY COPYRIGHT, 1911, BY DAVID EUGENE SMITH ALL RIGHTS BBSBBYBD ^1L6 GINN AND COMPANY " PRO-PRIETORS " BOSTON " U.S.A. PREFACE of A book upon the teaching geometry may be planned be ill divers ways. It may written to exploit a new theory of geometry, or a new method of presenting the science as we already have it. On the other hand, it may be ultraconservative, making a plea for the ancient teaching and the ancient geometry. It may be prepared fbr the purpose of setting forth the work as it now is, or with the tempting but dangerous idea of prophecy. of It may appeal to the iconoclast by its spirit destruc-tion, or to the disciples of laissez faire by its spirit of cbnserving what the past has bequeathed. It may be written for the few who always lead, or think they lead, or for the many who are ranked by the few as followers. And in view of these varied pathways into the joitit domain of geometry and education, a writer may well afford before he and to pause sets his pen to paper, to decide with care the route that he will take. At present in America we have a fairly well-defined body of matter in geometry, and this occupies a fairly iwrell-defined place in the curriculum. There are not wanting many earnest teachers who would change both the and radical fashion. matter the place in a very There are not wanting others, also many in number, who are content with things as they find them. But by far the largest part of the teaching body is of a mind to welcome the natural and gradual evolution of geometry toward better things, contributing to this evolution as iii iv PREFACE much as it can, glad to know the best that others have to offer,receptive of ideas that make for better teaching, but out of sympathy with either the extreme of revolu-tion or the extreme of stagnation. It is for this largerclass,the great body of progressive teachers, that this book is written. It stands for vitaliz-ing geometry in every legitimateway ; for improving the subject matter in such manner as not to destroy the pupil's interest ; for so teaching geometry as to make it appeal to pupils as strongly as any other subject in the curriculum; but for the recognition of geometry for geometry's sake and not for the sake of a fancied utility that hardly exists. Expressing full appreciation of the desirabilityof establishinga motive for all studies, so as to have the work proceed with interest and vigor,it does not hesitate to express doubt as to certain motives that have been exploited, nor to stand for such a genuine, thought-compelling development of the science as is in harmony with the* mental powers of the pupils in the American high school. For this class of teachers the author hopes that the book will prove of service, and that through its peru-sal they will come to admire the subject more and more, and to teach it with greater interest. It offers no pana-cea, it champions no single method, but it seeks to set forth plainly the reasons for teaching a geometry of the kind that we have inherited, and for hoping for a grad-ual but definite improvement in the science and in the methods of its presentation. DAVID EUGENE SMITH CONTENTS CHAPTER PAGE I. Certain Questions now at Issue 1 11. Why Geometry is studied 7 III. A Brief History of Geometry 26 IV. Development of the Teaching of Geometry 40 V. Euclid 47 VI. Efforts at Improving Euclid 57 VII. The Textbook in Geometry 70 VIII. The Relation of Algebra to Geometry 84 . IX. The Introduction to Geometry 93 X. The Conduct of a Class in Geometry 108 . XI. The Axioms and Postulates 116 XII. The Definitions of Geometry 132 XIII. How TO attack the Exercises 160 XIV. Book I and its Propositions 165 XV. The Leading Propositions of Book II 201 . XVI. The Leading Propositions of Book HI 227 . XVII. The Leading Propositions of Book IV 252 . XVIIL The Leading Propositions of Book V 269 . XIX. The Leading Propositions of Book VI 289 . XX. The Leading Propositions of Book VII 303 . XXI. The Leading Propositions of Book VIII 321 . INDEX 335 THE TEACHING OF GEOMETRY CHAPTER I CERTAIN QUESTIONS NOW AT ISSUE It is commonly said at the present time that the opening of the twentieth century is a period of unusual advancement in all that has to do with the school. It would be pleasant to feel that we are living in such an doubtful if the historian of educa-tion age, but it is future will find this to be the case, or that biographers will rank the leaders of our generation relatively as high as many who have passed away, or that any great movements of the present will be found that measure the world up to certain ones that now recognizes as epoch-making. Every generation since the invention of printing has been a period of agitation in educational matters, but out of all the noise and self-assertion, out of all the pretense of the chronic revolutionist, out of all the sham that leads to dogmatism, so little is remem-bered that we are apt to feel that the past had no prob-lems and was content simply to accept its inheritance. In one sense it is not a misfortune thus to be blinded by the dust of present agitation and to be deafened by the noisy clamor of the agitator, since it stirs us to action at finding ourselves in the midst of the skirmish ; but in another sense it is detrimental to Our progress, 1 2 THE TEACHING OF GEOMETRY since we thereby tend to lose the idea of perspective, and the coin comes to appear to our vision as large as the moon. In consideringa question like the teachingof geome-try, we at once find ourselves in the midst of a skirmish of this nature. If we jointhoughtlesslyin the noise,we may easilypersuade ourselves that we are waging a mighty battle,fightingfor some stupendous principle, doing deeds of great valor and of personal sacrifice. If, on the other hand, we stand aloof and think of the present movement as merely a chronic effervescence, fostered by the professionaleducator at the expense of the practicalteacher, we are equallyshortsighted.Sir Conan Doyle expressedthis sentiment most delightfully in these words : such The dead are good company that one may come to think too little of the living. It is a real and pressing danger with many of us that we should never find our own thoughts and our own souls,but be ever obsessed by the dead. In every generation it behooves the open-minded, earnest, progressiveteacher to seek for the best in the way of improvement, to endeavor to sift the few grains of gold out of the common dust, to weigh the values of proposed reforms, and to put forth his efforts to know and to use the best that the science of education has to offer. This has been the attitude of mind of the real leaders in the school life of the past, and it will be that of the leaders of the future. With these remarks to guide us, it is now proposed to take up the issues of the present day in the teaching of geometry, in order that we may consider them calmly and dispassionately,and may see where the opportunities for improvement lie. CERTAIN QUESTIONS NOW AT ISSUE 8 At the present time, in the educational circles of the United States,questionsof the followingtype are caus-ing the chief discussion among teachers of geometry : 1. Shall geometiy continue to be taught as an appli-cation of logic,or shall it be treated solelywith refer-ence to its applications? 2. If the latter is the purpose in view, shall the propositionsof geometry be limited to those that offer the an opportunityfor.real application,thus contracting whole subjectto very narrow dimensions ? 3. Shall a subjectcalled geometry be extended over several years, as 18 the case in Europe,^ or shall the name be appliedonly to serious demonstrative geome-try ^ as given in the second year of the four-yearhigh- school course in the United States at present? 4. Shall geometry be taught by itself,or shall it be either mixed with algebra (say a day of one subject followed by a day of the other)or fused with it in the form of a combined mathematics ? 5. Shall a textbook be used in which the basal propo-sitions are proved in full,the exercises furnishingthe opportunityfor originalwork and being looked upon as the most importantfeature,or shall one be employed in which the pupilis expectedto invent the proofsfor the basal propositionsas well as for the exercises ? " 6. Shall the terminologyand the spiritof a modified Euclid and Legendre prevailin the future as they have lAnd really,though not nominally, in the United States,where the first concepts are found in the kindergarten, and where an excellent course in mensuration is given in any of our better class of arithmetics. That we are wise in not attempting serious demonstrative geometry much earlier seems to be generally conceded. *The third stage of geometry as defined in the recent circular (No. 711) of the British Board' of Education, London, 1909.
Recommended publications
  • On the Standard Lengths of Angle Bisectors and the Angle Bisector Theorem
    Global Journal of Advanced Research on Classical and Modern Geometries ISSN: 2284-5569, pp.15-27 ON THE STANDARD LENGTHS OF ANGLE BISECTORS AND THE ANGLE BISECTOR THEOREM G.W INDIKA SHAMEERA AMARASINGHE ABSTRACT. In this paper the author unveils several alternative proofs for the standard lengths of Angle Bisectors and Angle Bisector Theorem in any triangle, along with some new useful derivatives of them. 2010 Mathematical Subject Classification: 97G40 Keywords and phrases: Angle Bisector theorem, Parallel lines, Pythagoras Theorem, Similar triangles. 1. INTRODUCTION In this paper the author introduces alternative proofs for the standard length of An- gle Bisectors and the Angle Bisector Theorem in classical Euclidean Plane Geometry, on a concise elementary format while promoting the significance of them by acquainting some prominent generalized side length ratios within any two distinct triangles existed with some certain correlations of their corresponding angles, as new lemmas. Within this paper 8 new alternative proofs are exposed by the author on the angle bisection, 3 new proofs each for the lengths of the Angle Bisectors by various perspectives with also 5 new proofs for the Angle Bisector Theorem. 1.1. The Standard Length of the Angle Bisector Date: 1 February 2012 . 15 G.W Indika Shameera Amarasinghe The length of the angle bisector of a standard triangle such as AD in figure 1.1 is AD2 = AB · AC − BD · DC, or AD2 = bc 1 − (a2/(b + c)2) according to the standard notation of a triangle as it was initially proved by an extension of the angle bisector up to the circumcircle of the triangle.
    [Show full text]
  • Advanced Euclidean Geometry
    Advanced Euclidean Geometry Paul Yiu Summer 2016 Department of Mathematics Florida Atlantic University July 18, 2016 Summer 2016 Contents 1 Some Basic Theorems 101 1.1 The Pythagorean Theorem . ............................ 101 1.2 Constructions of geometric mean . ........................ 104 1.3 The golden ratio . .......................... 106 1.3.1 The regular pentagon . ............................ 106 1.4 Basic construction principles ............................ 108 1.4.1 Perpendicular bisector locus . ....................... 108 1.4.2 Angle bisector locus . ............................ 109 1.4.3 Tangency of circles . ......................... 110 1.4.4 Construction of tangents of a circle . ............... 110 1.5 The intersecting chords theorem ........................... 112 1.6 Ptolemy’s theorem . ................................. 114 2 The laws of sines and cosines 115 2.1 The law of sines . ................................ 115 2.2 The orthocenter ................................... 116 2.3 The law of cosines .................................. 117 2.4 The centroid ..................................... 120 2.5 The angle bisector theorem . ............................ 121 2.5.1 The lengths of the bisectors . ........................ 121 2.6 The circle of Apollonius . ............................ 123 3 The tritangent circles 125 3.1 The incircle ..................................... 125 3.2 Euler’s formula . ................................ 128 3.3 Steiner’s porism ................................... 129 3.4 The excircles ....................................
    [Show full text]
  • 4 3 E B a C F 2
    See-Saw Geometry and the Method of Mass-Points1 Bobby Hanson February 27, 2008 Give me a place to stand on, and I can move the Earth. — Archimedes. 1. Motivating Problems Today we are going to explore a kind of geometry similar to regular Euclidean Geometry, involving points and lines and triangles, etc. The main difference that we will see is that we are going to give mass to the points in our geometry. We will call such a geometry, See-Saw Geometry (we’ll understand why, shortly). Before going into the details of See-Saw Geometry, let’s look at some problems that might be solved using this different geometry. Note that these problems are perfectly solvable using regular Euclidean Geometry, but we will find See-Saw Geometry to be very fast and effective. Problem 1. Below is the triangle △ABC. Side BC is divided by D in a ratio of 5 : 2, and AB is divided by E in a ration of 3 : 4. Find the ratios in which F divides the line segments AD and CE; i.e., find AF : F D and CF : F E. (Note: in Figure 1, below, only the ratios are shown; the actual lengths are unknown). B 3 E 5 4 F D 2 A C Figure 1 1My notes are shamelessly stolen from notes by Tom Rike, of the Berkeley Math Circle available at http://mathcircle.berkeley.edu/archivedocs/2007 2008/lectures/0708lecturespdf/MassPointsBMC07.pdf . 1 2 Problem 2. In Figure 2, below, D and E divide sides BC and AB, respectively, as before.
    [Show full text]
  • Icons of Mathematics an EXPLORATION of TWENTY KEY IMAGES Claudi Alsina and Roger B
    AMS / MAA DOLCIANI MATHEMATICAL EXPOSITIONS VOL 45 Icons of Mathematics AN EXPLORATION OF TWENTY KEY IMAGES Claudi Alsina and Roger B. Nelsen i i “MABK018-FM” — 2011/5/16 — 19:53 — page i — #1 i i 10.1090/dol/045 Icons of Mathematics An Exploration of Twenty Key Images i i i i i i “MABK018-FM” — 2011/5/16 — 19:53 — page ii — #2 i i c 2011 by The Mathematical Association of America (Incorporated) Library of Congress Catalog Card Number 2011923441 Print ISBN 978-0-88385-352-8 Electronic ISBN 978-0-88385-986-5 Printed in the United States of America Current Printing (last digit): 10987654321 i i i i i i “MABK018-FM” — 2011/5/16 — 19:53 — page iii — #3 i i The Dolciani Mathematical Expositions NUMBER FORTY-FIVE Icons of Mathematics An Exploration of Twenty Key Images Claudi Alsina Universitat Politecnica` de Catalunya Roger B. Nelsen Lewis & Clark College Published and Distributed by The Mathematical Association of America i i i i i i “MABK018-FM” — 2011/5/16 — 19:53 — page iv — #4 i i DOLCIANI MATHEMATICAL EXPOSITIONS Committee on Books Frank Farris, Chair Dolciani Mathematical Expositions Editorial Board Underwood Dudley, Editor Jeremy S. Case Rosalie A. Dance Tevian Dray Thomas M. Halverson Patricia B. Humphrey Michael J. McAsey Michael J. Mossinghoff Jonathan Rogness Thomas Q. Sibley i i i i i i “MABK018-FM” — 2011/5/16 — 19:53 — page v — #5 i i The DOLCIANI MATHEMATICAL EXPOSITIONS series of the Mathematical As- sociation of America was established through a generous gift to the Association from Mary P.
    [Show full text]
  • Foundations of Euclidean Constructive Geometry
    FOUNDATIONS OF EUCLIDEAN CONSTRUCTIVE GEOMETRY MICHAEL BEESON Abstract. Euclidean geometry, as presented by Euclid, consists of straightedge-and- compass constructions and rigorous reasoning about the results of those constructions. A consideration of the relation of the Euclidean “constructions” to “constructive mathe- matics” leads to the development of a first-order theory ECG of “Euclidean Constructive Geometry”, which can serve as an axiomatization of Euclid rather close in spirit to the Elements of Euclid. Using Gentzen’s cut-elimination theorem, we show that when ECG proves an existential theorem, then the things proved to exist can be constructed by Eu- clidean ruler-and-compass constructions. In the second part of the paper we take up the formal relationships between three versions of Euclid’s parallel postulate: Euclid’s own formulation in his Postulate 5, Playfair’s 1795 version, which is the one usually used in modern axiomatizations, and the version used in ECG. We completely settle the questions about which versions imply which others using only constructive logic: ECG’s version im- plies Euclid 5, which implies Playfair, and none of the reverse implications are provable. The proofs use Kripke models based on carefully constructed rings of real-valued functions. “Points” in these models are real-valued functions. We also characterize these theories in terms of different constructive versions of the axioms for Euclidean fields.1 Contents 1. Introduction 5 1.1. Euclid 5 1.2. The collapsible vs. the rigid compass 7 1.3. Postulates vs. axioms in Euclid 9 1.4. The parallel postulate 9 1.5. Polygons in Euclid 10 2.
    [Show full text]
  • The Postulates of Neutral Geometry Axiom 1 (The Set Postulate). Every
    1 The Postulates of Neutral Geometry Axiom 1 (The Set Postulate). Every line is a set of points, and the collection of all points forms a set P called the plane. Axiom 2 (The Existence Postulate). There exist at least two distinct points. Axiom 3 (The Incidence Postulate). For every pair of distinct points P and Q, there exists exactly one line ` such that both P and Q lie on `. Axiom 4 (The Distance Postulate). For every pair of points P and Q, the distance from P to Q, denoted by P Q, is a nonnegative real number determined uniquely by P and Q. Axiom 5 (The Ruler Postulate). For every line `, there is a bijective function f : ` R with the property that for any two points P, Q `, we have → ∈ P Q = f(Q) f(P ) . | − | Any function with these properties is called a coordinate function for `. Axiom 6 (The Plane Separation Postulate). If ` is a line, the sides of ` are two disjoint, nonempty sets of points whose union is the set of all points not on `. If P and Q are distinct points not on `, then both of the following equivalent conditions are satisfied: (i) P and Q are on the same side of ` if and only if P Q ` = ∅. ∩ (ii) P and Q are on opposite sides of ` if and only if P Q ` = ∅. ∩ 6 Axiom 7 (The Angle Measure Postulate). For every angle ∠ABC, the measure of ∠ABC, denoted by µ∠ABC, isa real number strictly between 0 and 180, determined uniquely by ∠ABC. Axiom 8 (The Protractor Postulate).
    [Show full text]
  • The Steiner-Lehmus Theorem an Honors Thesis
    The Steiner-Lehmus Theorem An Honors ThesIs (ID 499) by BrIan J. Cline Dr. Hubert J. LudwIg Ball State UniverSity Muncie, Indiana July 1989 August 19, 1989 r! A The Steiner-Lehmus Theorem ; '(!;.~ ,", by . \:-- ; Brian J. Cline ProposItion: Any triangle having two equal internal angle bisectors (each measured from a vertex to the opposite sIde) is isosceles. (Steiner-Lehmus Theorem) ·That's easy for· you to say!- These beIng the possible words of a suspicIous mathematicIan after listenIng to some assumIng person state the Steiner-Lehmus Theorem. To be sure, the Steiner-Lehmus Theorem Is ·sImply stated, but notoriously difficult to prove."[ll Its converse, the bIsectors of the base angles of an Isosceles trIangle are equal, Is dated back to the tIme of EuclId and is easy to prove. The Steiner-Lehmus Theorem appears as if a proof would be simple, but it is defInItely not.[2l The proposition was sent by C. L. Lehmus to the Swiss-German geometry genIus Jacob SteIner in 1840 with a request for a pure geometrIcal proof. The proof that Steiner gave was fairly complex. Consequently, many inspIred people began searchIng for easier methods. Papers on the Steiner-Lehmus Theorem were prInted in various Journals in 1842, 1844, 1848, almost every year from 1854 untIl 1864, and as a frequent occurence during the next hundred years.[Sl In terms of fame, Lehmus dId not receive nearly as much as SteIner. In fact, the only tIme the name Lehmus Is mentIoned In the lIterature Is when the title of the theorem is gIven. HIs name would have been completely forgotten if he had not sent the theorem to Steiner.
    [Show full text]
  • The Calculus: a Genetic Approach / Otto Toeplitz ; with a New Foreword by David M
    THE CALCULUS THE CALCULUS A Genetic Approach OTTO TOEPLITZ New Foreword by David Bressoud Published in Association with the Mathematical Association of America The University of Chicago Press Chicago · London The present book is a translation, edited after the author's death by Gottfried Kothe and translated into English by LuiseLange. The German edition, DieEntwicklungder Infinitesimalrechnung,was published by Springer-Verlag. The University of Chicago Press,Chicago 60637 The University of Chicago Press,ltd., London © 1963 by The University of Chicago Foreword © 2007 by The University of Chicago All rights reserved. Published 2007 Printed in the United States of America 16 15 14 13 12 11 10 09 08 07 2 3 4 5 ISBN-13: 978-0-226-80668-6 (paper) ISBN-10: 0-226-80668-5 (paper) Library of Congress Cataloging-in-Publication Data Toeplitz, Otto, 1881-1940. [Entwicklung der Infinitesimalrechnung. English] The calculus: a genetic approach / Otto Toeplitz ; with a new foreword by David M. Bressoud. p. cm. Includes bibliographical references and index. ISBN-13: 978-0-226-80668-6 (pbk. : alk. paper) ISBN-10: 0-226-80668-5 (pbk. : alk. paper) 1. Calculus. 2. Processes, Infinite. I. Title. QA303.T64152007 515-dc22 2006034201 § The paper used in this publication meets the minimum requirements of the American National Standard for Information Sciences-Permanence of Paper for Printed Library Materials, ANSI Z39.48-1992. FOREWORDTO THECALCULUS: A GENETICAPPROACHBYOTTO TOEPLITZ September 30, 2006 Otto Toeplitz is best known for his contributions to mathematics, but he was also an avid student of its history. He understood how useful this history could be in in­ forming and shaping the pedagogy of mathematics.
    [Show full text]
  • View This Volume's Front and Back Matter
    Continuou s Symmetr y Fro m Eucli d to Klei n This page intentionally left blank http://dx.doi.org/10.1090/mbk/047 Continuou s Symmetr y Fro m Eucli d to Klei n Willia m Barke r Roge r How e >AMS AMERICAN MATHEMATICA L SOCIET Y Freehand® i s a registere d trademar k o f Adob e System s Incorporate d in th e Unite d State s and/o r othe r countries . Mathematica® i s a registere d trademar k o f Wolfra m Research , Inc . 2000 Mathematics Subject Classification. Primar y 51-01 , 20-01 . For additiona l informatio n an d update s o n thi s book , visi t www.ams.org/bookpages/mbk-47 Library o f Congres s Cataloging-in-Publicatio n Dat a Barker, William . Continuous symmetr y : fro m Eucli d t o Klei n / Willia m Barker , Roge r Howe . p. cm . Includes bibliographica l reference s an d index . ISBN-13: 978-0-8218-3900- 3 (alk . paper ) ISBN-10: 0-8218-3900- 4 (alk . paper ) 1. Geometry, Plane . 2 . Group theory . 3 . Symmetry groups . I . Howe , Roger , 1945 - QA455.H84 200 7 516.22—dc22 200706079 5 Copying an d reprinting . Individua l reader s o f thi s publication , an d nonprofi t librarie s acting fo r them , ar e permitted t o mak e fai r us e o f the material , suc h a s to cop y a chapter fo r us e in teachin g o r research .
    [Show full text]
  • Exploring Euclidean Geometry
    Dennis Chen’s Exploring Euclidean Geometry A S I B C D E T M X IA Dennis Chen Last updated August 8, 2020 Exploring Euclidean Geometry V2 Dennis Chen August 8, 2020 1 Introduction This is a preview of Exploring Euclidean Geometry V2. It contains the first five chapters, which constitute the entirety of the first part. This should be a good introduction for those training for computational geometry questions. This book may be somewhat rough on beginners, so I do recommend using some slower-paced books as a supplement, but I believe the explanations should be concise and clear enough to understand. In particular, a lot of other texts have unnecessarily long proofs for basic theorems, while this book will try to prove it as clearly and succintly as possible. There aren’t a ton of worked examples in this section, but the check-ins should suffice since they’re just direct applications of the material. Contents A The Basics3 1 Triangle Centers 4 1.1 Incenter................................................4 1.2 Centroid................................................5 1.3 Circumcenter.............................................6 1.4 Orthocenter..............................................7 1.5 Summary...............................................7 1.5.1 Theory............................................7 1.5.2 Tips and Strategies......................................8 1.6 Exercises...............................................9 1.6.1 Check-ins...........................................9 1.6.2 Problems...........................................9
    [Show full text]
  • |||GET||| Geometry Theorems and Constructions 1St Edition
    GEOMETRY THEOREMS AND CONSTRUCTIONS 1ST EDITION DOWNLOAD FREE Allan Berele | 9780130871213 | | | | | Geometry: Theorems and Constructions For readers pursuing a career in mathematics. Angle bisector theorem Exterior angle theorem Euclidean algorithm Euclid's theorem Geometric mean theorem Greek geometric algebra Hinge theorem Inscribed Geometry Theorems and Constructions 1st edition theorem Intercept theorem Pons asinorum Pythagorean theorem Thales's theorem Theorem of the gnomon. Then the 'construction' or 'machinery' follows. For example, propositions I. The Triangulation Lemma. Pythagoras c. More than editions of the Elements are known. Euclidean geometryelementary number theoryincommensurable lines. The Mathematical Intelligencer. A History of Mathematics Second ed. The success of the Elements is due primarily to its logical presentation of most of the mathematical knowledge available to Euclid. Arcs and Angles. Applies and reinforces the ideas in the geometric theory. Scholars believe that the Elements is largely a compilation of propositions based on books by earlier Greek mathematicians. Enscribed Circles. Return for free! Description College Geometry offers readers a deep understanding of the basic results in plane geometry and how they are used. The books cover plane and solid Euclidean geometryelementary number theoryand incommensurable lines. Cyrene Library of Alexandria Platonic Academy. You can find lots of answers to common customer questions in our FAQs View a detailed breakdown of our shipping prices Learn about our return policy Still need help? View a detailed breakdown of our shipping prices. Then, the 'proof' itself follows. Distance between Parallel Lines. By careful analysis of the translations and originals, hypotheses have been made about the contents of the original text copies of which are no longer available.
    [Show full text]
  • New Editor-In-Chief for CRUX with MAYHEM
    1 New Editor-in-Chief for CRUX with MAYHEM We happily herald Shawn Godin of Cairine Wilson Secondary School, Orleans, ON, Canada as the next Editor-in-Chief of Crux Mathematicorum with Mathematical Mayhem effective 21 March 2011. With this issue Shawn takes the reins, and though some of you know Shawn as a former Mayhem Editor let me provide some further background. Shawn grew up outside the small town of Massey in Northern On- tario. He obtained his B. Math from the University of Waterloo in 1987. After a few years trying to decide what to do with his life Shawn returned to school obtaining his B.Ed. in 1991. Shawn taught at St. Joseph Scollard Hall S.S. in North Bay from 1991 to 1998. During this time he married his wife Julie, and his two sons Samuel and Simon were born. In the summer of 1998 he moved with his family to Orleans where he has taught at Cairine Wilson S.S. ever since (with a three year term at the board office as a consultant). He also managed to go back to school part time and earn an M.Sc. in mathematics from Carleton University in 2002. Shawn has been involved in many mathematical activities. In 1998 he co-chaired the provincial mathematics education conference. He has been involved with textbook companies developing material for teacher resources and the web as well as writing a few chapters for a grade 11 textbook. He has developed materials for teachers and students for his school board, as well as the provincial ministry of education.
    [Show full text]