Log in

View Full Version : Pi and the area of circles


kickflip2005
Apr 22, 2005, 09:58 PM
as I'm sure u all know, pi is so far an infinite decimal (3.1415... )

when you are finding the area of a circle (pi*r^2), you usually get a long decimal, then round

with pi being indefinite, is it impossible to have a circle with an even area?

just wondring,

brook

CroCivic91
Apr 23, 2005, 04:21 AM
It is not impossible. If you want the area of a circle which is P=pi*r^2 to be a natural number, you just have to have such radius that when squared and multiplied by pi will give you a natural number. So if you take a cricle with radius r=1/(square root of pi) and calculate it's "area", you will get P=pi*(1/((square root of pi)^2)) which is P=pi*1/pi which is P=1.

In the same way, if you want a circle to have an "area" of X then just take such circle that has radius r=square root of (X/pi).