Facts about Pi
Date: 03/09/97 at 17:37:53 From: Anonymous Subject: pi What are a few interesting facts about pi?
Date: 03/11/97 at 10:31:05 From: Doctor Ken Subject: Re: pi Hi there, Pi was known by the Egyptians, who calculated it to be approximately (4/3)^4 which equals 3.1604. The earliest known reference to pi occurs in a Middle Kingdom papyrus scroll, written around 1650 BC by a scribe named Ahmes. He began the scroll with the words: "The Entrance Into the Knowledge of All Existing Things" and remarked in passing that he composed the scroll "in likeness to writings made of old." Toward the end of the scroll, which is composed of various mathematical problems and their solutions, the area of a circle is found using a rough sort of pi. Around 200 BC, Archimedes of Syracuse found that pi is somewhere about 3.14 (in fractions; Greeks did not have decimals). Pi (which is a letter in the Greek alphabet) was discovered by a Greek mathematician named Archimedes. Archimedes wrote a book called The Measurement of a Circle. In the book he states that Pi is a number between 3 10/71 and 3 1/7. He figured this out by taking a polygon with 96 sides and inscribing a circle inside the polygon. That was Archemedes' concept of Pi. New knowledge of Pi then bogged down until the 17th century. Pi was then called the Ludolphian number, after Ludolph van Ceulen, a German mathematician. The first person to use the Greek letter Pi for the number was William Jones, an English mathematician, who coined it in 1706. In the 1800's people sat down for years on end to find the values of pi to about 1000 places. Imagine doing this by hand with no calculators. This has become a thing of the past, since the tedium that used to be done by hand is now done by computer. Facts About Pi - Pi is the ratio of the circumference of a circle to the diameter. - 2 Pi in radians form is 360 degrees. Therefore Pi radians is 180 degrees and 1/2 Pi radians is 90 degrees. - e raised to the i*pi power equals -1 (e is the base of the natural logarithm and i is the imaginary number which is the sqare root of -1). - Pi day is celebrated on March 14 at the Exploratorium in San Francisco (March 14 is 3/14). - All the digits of Pi can never be fully known. For more about Pi see the Dr. Math FAQ: http://mathforum.org/dr.math/faq/faq.pi.html - Doctor Ken, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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