Squaring the Circle
Date: 3/16/96 at 21:44:27 From: Deborah A. Lindsay Subject: math question Dr. Math, Where did the phrase "squaring the circle" come from? We found it in literature and wonder about its origins and what it means. Thank you. (United States House of Representatives Page School)
Date: 3/17/96 at 1:22:24 From: Doctor Jodi Subject: Re: math question Hello! Thanks for your question. The Greeks were great at posing mathematical questions that no one could solve. One of these questions was: Using only a straight edge and compass, construct a square with the same area as a circle. The Greeks tried to solve this by construction as early as 200 BC. From this problem comes the phrase you ask about, "squaring the circle". Now, we know that the constant that relates the area of a circle and its perimeter to the radius, pi (usally represented by the Greek letter of the same name), is a transcendental number. Transcendental, you say, that's an interesting name for a number, but what does it mean? Well, a transcendental number is one that can't be expressed as a ratio of two integers AND it can't be expressed as a terminating decimal, like 1.09 or a non-terminating decimal with a pattern: i.e. 0.3333333, etc. or 1.297297297297, etc. In fact, we have calculated a few MILLION digits for pi and we still find it to be transcendental. But more importantly, people have proven that pi is transcendental. I think that the first proof of this was by Lindemann in 182 (described in Courant and Robbins' _What is Mathematics_). So that ancient problem which so many people have struggled with, squaring the circle, is not possible with just compass and straight edge. Hope that this answers your question... I'm really curious about what the Page School is (a school for would-be pages? for the children of House members?) -Doctor Jodi, The Math Forum
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