Want to try calculating it yourself? Try one of these infinite series formulas...

π = (4/1) - (4/3) + (4/5) - (4/7) + (4/9) - (4/11) + (4/13) - (4/15) ...

π = 3 + 4/(2*3*4) - 4/(4*5*6) + 4/(6*7*8) - 4/(8*9*10) + 4/(10*11*12) - 4/(12*13*14) ...

• RE: Happy Pi day!,kingfish, 10:39 AM, 03-14-17
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• RE: Happy Pi day!,foonermints, 11:15 AM, 03-16-17
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    • Fresh Peaches!,foonermints, 10:54 PM, 03-16-17
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• RE: Happy Pi day!,foonermints, 04:14 PM, 03-25-17
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Since Pi is the ratio of the circumference of a circle to it's diameter, how do those equations represent Pi?

Through The Mystery of the Apple of course.

Unless you prefer Peach. I kind of like Peach..

The first formula π = (4/1) - (4/3) + (4/5) - (4/7) + (4/9) - (4/11) + (4/13) - (4/15) ... is known as the Madhava–Leibniz series. It starts with the fact that π/4 = arctan(1), which is a geometric expression that is converted into the infinite series algebraic expression.

You'll find the proof for the first formula here. That Madhava fellow is a 14th century Indian mathematician known as Madhava of Sangamagrama (try saying that out loud!)

The second formula π = 3 + 4/(2*3*4) - 4/(4*5*6) + 4/(6*7*8) - 4/(8*9*10) + 4/(10*11*12) - 4/(12*13*14) ... is known as the Nilakantha series. That Nilakantha fellow is 15th century Indian mathematician-astronomer Kelallur Nilakantha Somayaji based in Karala, India.

If you really want to make your head swim (like a real fish), you'll find an academic paper on this topic that describes how both of these formulas are derived and proven.

LAST EDITED ON 03-14-17 AT 02:38 PM (EST)

I'm not a mathematician, and can't begin to follow the connections that the infinite series formulae you quote have with the ratio of a circle's circumference to it's diameter, but even to a simple fish brain, Pi=circumference/diameter. Why should anyone make it unnecessarily obtuse?

Make mine pecan.

LAST EDITED ON 03-14-17 AT 09:54 PM (EST)

Perhaps one of the most elegant equations in mathematics that uses is π is Euler's identity:

e^iπ + 1 = 0

This equation neatly ties in π, i as the square root of -1, e as base of the natural logarithm, one and zero.

But maybe you can wrap your head around this simplest of equations:

sin π = 0

Neither are proofs. They are both identities. Or perhaps the second is a function.

And Euler's formula doesn't really seem that neat because the square root of -1 is imaginary.

But still, why isn't the equation that defines Pi (Pi=Circ/Dia) the clearest and simplest to use? It requires no proof since it is the defining relationship.

The universal contestants are best expressed in the simplest terms.

Mass in = Mass out.

Action = reaction.

Trig functions.

I guess I have to accept that mathematicians don't like tape measures.

It was Kurt Gödel who aaid that you can't necessarily prove all of the truths of a mathematical system, nor are such mathematical systems fully consistent within themselves.

I remember hating to do proofs in math class in high school. Either it's true or it ain't, no need to go through long-winded deductive arguments based on some arcane axiomatic system to demonstrate it, right?

Tape measures are fine, but a string might work better. But legislators who try to define pi by law are another thing entirely, as tried in Indiana in 1897.

Oh, by the way... do you know who's birthday it is?

That the Tongue of the Buffalo is the tastiest. That's just word-on-the-street, obviously.

Canadians and Alaskans swear by Caribou tongue. That's right, they would eat the tongue right out of Rudolph's mouth.

I can still get 1/2 off Bristol Farms pies. Should I get one?

I'm switching to peach.

(Very slow on the double entendres lately)

Mmmmmm.

Decorate that pie?

I just got this Pie. I wonder if it's any good?

CTgirl Chupacabra!
*kicks another worthless spammer off front page..