{"id":3594,"date":"2023-11-23T07:51:08","date_gmt":"2023-11-23T12:51:08","guid":{"rendered":"https:\/\/sites.williams.edu\/Morgan\/?page_id=3594"},"modified":"2023-11-23T07:52:39","modified_gmt":"2023-11-23T12:52:39","slug":"a-one-page-proof-of-fermat","status":"publish","type":"page","link":"https:\/\/sites.williams.edu\/Morgan\/math-chat-archives\/a-one-page-proof-of-fermat\/","title":{"rendered":"A ONE-PAGE PROOF OF FERMAT?"},"content":{"rendered":"<p>February 18, 1999<\/p>\n<h3><\/h3>\n<p><b>MATH JOKES.\u00a0<\/b>Math Chat has received a number of mathematical jokes, most of them terrible. This week&#8217;s winner is a riddle from Peter Hegarty:<\/p>\n<p><b>RIDDLE.\u00a0<\/b>Which mathematical term is named after a well-known American politician?<\/p>\n<p>The answer is near the end of this column.<\/p>\n<p><b>OLD CHALLENGE\u00a0<\/b>(Joe Shipman). Select the best occurrence in the world of each number from 1 to 10. For example, 12 is the number of eggs in a dozen or the number of months in a year.<\/p>\n<p><b>ANSWER.\u00a0<\/b>Here is the winning response compiled from John Robertson, Henry Ricardo, Bob Swanson, Jean-Pierre Carmichael, and Ryan Grove:<\/p>\n<p>&nbsp;<\/p>\n<ol>\n<li>Number of Earth&#8217;s moons<\/li>\n<li>Romeo and Juliet<\/li>\n<li>Dimensions; Mazur, Ribet, and Wiles (contributors to the proof of Fermat&#8217;s Last Theorem)<\/li>\n<li>The Four Freedoms (FDR, 1941: freedom of speech, freedom of worship, freedom from want, freedom from fear)<\/li>\n<li>Platonic solids [cube, octahedron, tetrahedron, dodecahedron, icosahedron]<\/li>\n<li>Legs on insects<\/li>\n<li>Notes of the musical scale<\/li>\n<li>Cylinders in a V8 engine (such as in the Ferrari 308 series); vegetables in V8 juice (tomatoes, carrots, celery, beets, parsley, lettuce, watercress, and spinach)<\/li>\n<li>Planets; Beethoven symphonies<\/li>\n<li>Fingers<\/li>\n<\/ol>\n<p>(Can readers improve on this list?) Then there is this from Al Zimmermann:<\/p>\n<p>&nbsp;<\/p>\n<ol>\n<li>The amount, in cents, of the recent postage increase for first class US mail.<\/li>\n<li>The number of sides to every story.<\/li>\n<li>The number of moving parts in a Wankel engine.<\/li>\n<li>The number of Beatles.<\/li>\n<li>The number of players on a basketball team.<\/li>\n<li>The number of sodas in a six-pack.<\/li>\n<li>The number of days in a week.<\/li>\n<li>The number of days in a week, according to the Beatles.<\/li>\n<li>The number of months in a pregnancy.<\/li>\n<li>The number of years it seems the Clinton\/Lewinsky scandal has been going on.<\/li>\n<\/ol>\n<p>Finally, in his beautiful response, David Shay relates that, &#8220;At the end of the Seder night, which begins the Jewish holiday of Passover, it is common to sing a song named &#8216;Who Knows One.&#8217; This song gives an exact Jewish answer to your challenge, in the range of 1 to 13. Here it is:<\/p>\n<p>&nbsp;<\/p>\n<p style=\"padding-left: 80px\">Thirteen are the attributes of God;<\/p>\n<p style=\"padding-left: 80px\">Twelve are the tribes of Israel;<\/p>\n<p style=\"padding-left: 80px\">Eleven were the stars in Joseph&#8217;s dream;<\/p>\n<p style=\"padding-left: 80px\">Ten commandments were given on Sinai;<\/p>\n<p style=\"padding-left: 80px\">Nine is the number of the holidays;<\/p>\n<p style=\"padding-left: 80px\">Eight are the days to the service of the covenant;<\/p>\n<p style=\"padding-left: 80px\">Seven days there are in a week;<\/p>\n<p style=\"padding-left: 80px\">Six sections the Mishnah has;<\/p>\n<p style=\"padding-left: 80px\">Five books there are in the Torah;<\/p>\n<p style=\"padding-left: 80px\">Four is the number of the matriarchs;<\/p>\n<p style=\"padding-left: 80px\">Three is the number of the patriarchs;<\/p>\n<p style=\"padding-left: 80px\">Two are the tables of the covenant;<\/p>\n<p style=\"padding-left: 80px\">One is our God in heaven and earth.&#8221;<\/p>\n<p>&nbsp;<\/p>\n<p><b>NEW CHALLENGE.\u00a0<\/b>Critique the following short proof of Fermat&#8217;s Last Theorem sent in by reader Rob Connelly. (In perhaps the biggest mathematics news of the century, Andrew Wiles recently came up with a very long and complicated proof to this 350-year old problem.)<\/p>\n<p>Fermat&#8217;s Last Theorem. The equation<\/p>\n<p>(1) x<sup>n<\/sup>\u00a0+ y<sup>n<\/sup>\u00a0= z<sup>n<\/sup>\u00a0has no positive integer solutions for n &gt; 2.<\/p>\n<p>Proposed proof. Suppose there were such a solution. Since x\u00a0<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/mathchat.org\/not.gif\" alt=\"not equal sign\" width=\"9\" height=\"8\" \/>\u00a0y, we may suppose x = y + a, z = y + b, with b &gt; a positive integers. Consider the integer N defined by<\/p>\n<p>(2) z<sup>n -1<\/sup>\u00a0= x<sup>n -1<\/sup>\u00a0+ y<sup>n -1<\/sup>\u00a0+ N.<\/p>\n<p>Then<\/p>\n<p>x<sup>n<\/sup>\u00a0+ y<sup>n<\/sup>\u00a0= z<sup>n<\/sup>\u00a0= z(x<sup>n -1<\/sup>\u00a0+ y<sup>n -1\u00a0<\/sup>+ N).<\/p>\n<p>Solving for N yields:<\/p>\n<p>N = [(y+a)\u00a0<sup>n -1<\/sup>\u00a0(a-b) + y<sup>n -1<\/sup>\u00a0(-b)]\/(y+b) = [F(y)]\/(y+b) ,<\/p>\n<p>so y+b divides F(y) and<\/p>\n<p>0 = F(-b) = (a-b)\u00a0<sup>n\u00a0<\/sup>+ (-b)\u00a0<sup>n<\/sup><\/p>\n<p>0 = (b-a)\u00a0<sup>n\u00a0<\/sup>+ b<sup>n<\/sup>\u00a0&gt; 0,<\/p>\n<p>the desired contradiction.<\/p>\n<p><b>ANSWER TO RIDDLE.<\/b>\u00a0The mathematical term named after a well-known American politician is &#8220;Algorithm.&#8221; (Readers are invited to continue to submit more jokes for future columns.)<\/p>\n<p>Send answers, comments, and new questions by email to:<\/p>\n<p><a href=\"mailto:Frank.Morgan@williams.edu\">Frank.Morgan@williams.edu<\/a>, to be eligible for\u00a0<i>Flatland<\/i>\u00a0and other book awards. Winning answers will appear in the next Math Chat. Math Chat appears on the first and third Thursdays of each month. Prof. Morgan&#8217;s homepage is at\u00a0<a href=\"http:\/\/www.williams.edu\/Mathematics\/fmorgan\">www.williams.edu\/Mathematics\/fmorgan<\/a>.<\/p>\n<p>Copyright 1999, Frank Morgan.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>February 18, 1999 MATH JOKES.\u00a0Math Chat has received a number of mathematical jokes, most of them terrible. This week&#8217;s winner is a riddle from Peter Hegarty: RIDDLE.\u00a0Which mathematical term is named after a well-known American politician? The answer is near the end of this column. OLD CHALLENGE\u00a0(Joe Shipman). Select the best occurrence in the world [&hellip;]<\/p>\n","protected":false},"author":2965,"featured_media":0,"parent":3459,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-3594","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/pages\/3594","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/users\/2965"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/comments?post=3594"}],"version-history":[{"count":4,"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/pages\/3594\/revisions"}],"predecessor-version":[{"id":3598,"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/pages\/3594\/revisions\/3598"}],"up":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/pages\/3459"}],"wp:attachment":[{"href":"https:\/\/sites.williams.edu\/Morgan\/wp-json\/wp\/v2\/media?parent=3594"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}