Pi: Exact Number vs. Unending Representation
Date: 09/15/2004 at 21:58:24 From: Amanda Subject: pi If pi is a number that doesn't end how is it that pi is an exact number on the number line? If the number doesn't end how can it be an exact number?
Date: 09/15/2004 at 22:44:16 From: Doctor Luis Subject: Re: pi Hi Amanda, You've hit on a two thousand year old question! The reason it's still an exact number is that each decimal that keeps getting added is smaller and smaller. They get so small, that even after you add an infinite number of them, they don't grow the number by that much. Eventually, you just end up with the excact number pi. Conceptually, this is related to Zeno's Paradox. Zeno was a philosopher who lived a long time ago in Greece, and didn't believe that you could add up a bunch of small numbers and end up with something that isn't infinite. Fortunately for us, he was wrong, or we wouldn't be able to walk anywhere. What do I mean by this? You should probably take a look at our archives, where Doctor Mike takes on that very question: Halving and Halving Again - Zeno's Paradox http://mathforum.org/library/drmath/view/52507.html I hope this helped! Let us know if you have other thought-provoking questions. - Doctor Luis, The Math Forum http://mathforum.org/dr.math/
Date: 09/16/2004 at 19:44:42 From: Amanda Subject: Thank you (pi) Dear Doctor Luis, Thank you very much for answering my question. I greatly appreciate it. Amanda
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