Ten Facts about Pi
Date: 09/15/2002 at 20:42:09 From: Christy Subject: Ten facts about pi I know nothing about pi. I'm supposed to research 10 facts about pi. Thank you.
Date: 09/18/2002 at 21:18:46 From: Doctor Nitrogen Subject: Re: Ten facts about pi Hi Christy, Here are ten facts about pi: 1. Pi is used to calculate the area and volumes of a wide variety of two-dimensional and three-dimensional geometrical objects. To see what some of them are, you can go to the Geometric Formulas section of the Dr. Math FAQ: http://mathforum.org/dr.math/faq/formulas/ Look under Circle, Cone, and Sphere for starters. 2. The decimal expansion of pi never terminates. 3. One area of mathematical interest is computing pi to as many decimals as a computer can handle. At PiHex - A distributed effort to calculate Pi http://www.cecm.sfu.ca/projects/pihex/ you can find various "distributed computing" projects where pi was calculated for huge numbers of decimal digits. One such project you will see there calculated pi up to 40 trillion decimal digits. 4. Throughout history, various civilizations obtained different values for pi. For instance, in the Bible, the Israelites approximated pi simply as the number 3. The ancient Greek scientist Archimedes also got several approximations for pi. 5. There was a British mathematician named Hardy who was a kind of "sponsor" of Srinivasa Ramanujan, a man who came up with cool formulas by which pi could be quickly calculated. 6. Pi is used extensively in trigonometry. 7. Pi is used extensively by scientists and engineers. 8. There are circles you can draw on the surface of a sphere for which the ratio of the circumference of that circle to its diameter will not equal pi. This gets into General Relativity Theory. You can read more about this in the Dr. Math archives: Einstein, Curved Space, and Pi http://mathforum.org/library/drmath/view/55198.html 9. If you try to draw a circle on a saddle surface, the ratio of the circumference to the diameter will also not equal pi, for a similar reason as applies in (8) above. 10. Pi will never be the root of any polynomial equation. I hope this helps! For general information about pi, see the Dr. Math FAQ: About Pi http://mathforum.org/dr.math/faq/faq.pi.html - Doctors Nitrogen and Sarah, The Math Forum http://mathforum.org/dr.math/
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