Exact pi?


By Robert Bartlett (M723) on Wednesday, September 27, 2000 - 09:56 am :
Pi (p) is the ratio of a circle's circumference divided by its diameter, but since real physical measurements are never perfect what alternate method is used to derive the EXACT value (or more precisely the infinitely running string of numeric digits that comprise p)?
By Marcus Hill (T3280) on Wednesday, September 27, 2000 - 06:30 pm :

There are any number of infinite series which can be proved to converge to pi (or some multiple thereof), some very slowly, others quickly. One can calculate the value of pi to any accuracy one pleases by evaluating sufficient terms in these series.


By Dave Sheridan (Dms22) on Thursday, September 28, 2000 - 10:31 am :
That is to say, p is much more fundamental to mathematics than simply being the ratio of a circle's circumference to its diameter. It happens to pop up in many different places and this allows us to obtain the infinite series which Marcus mentioned. One of the main reasons is that angles are measured in radians (rather than degrees) which happens to be a much more natural way to deal with them, and radians go from 0 to 2p rather than degrees which are 0 to 360. This links trigonometry to radians, and the trig functions (as well as many others) are much simpler to understand if they're looked at in radians.

-Dave


By The Editor :

Have a look at the Joy of Pi site. It has lots of links to sites with information about pi.
There are some formulas for calculating pi here .