pi/4 = 4arctan(1/5) - arctan(1/239)
2007-03-19 16:49:41
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answer #1
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answered by tryzub91 3
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Pi = 4 arctan(1)
Pi = 6arctan(1/sqrt(3))
Pi = 3arctan(sqrt(3))
Pi = 2(arctan(x) + arctan(1/x)) if x >0 (you can plug in anything for x! 100, 147.325, it doesn't matter, as long as it's positive)
2007-03-19 23:49:53
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answer #2
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answered by mitch w 2
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4 arctan 1 = pi
This and many others from
http://www.primepuzzles.net/puzzles/puzz_050.htm
The formula involving arctan can be found by scrolling about 2/3 of the way down the page. There are many good approximation formulas on this page, enjoy!
2007-03-19 23:49:28
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answer #3
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answered by Joni DaNerd 6
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There are LOTS of such formulas. Tryzub91 (answerer 3) should get "Best Answer" because he gave one of the best and most popular, called Machin's formula:
pi/4 = 4 x arctan(1/5) - arctan(1/239)
2007-03-20 08:50:13
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answer #4
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answered by bh8153 7
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ArcTan(1) = Ï/4, because the tangent of 45° is 1. You can take it from there.
2007-03-19 23:50:54
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answer #5
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answered by Scythian1950 7
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tan Ï/4 = 1
arctan tan Ï/4 = arctan 1
Ï/4 = arctan 1
Ï = 4 arctan 1
2007-03-19 23:52:12
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answer #6
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answered by novangelis 7
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I would guess that 2*tan^-1(0) would equal PI, but I could be wrong.
2007-03-19 23:47:50
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answer #7
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answered by Anonymous
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