Finding a Circle's Area Without PiDate: 02/24/2001 at 22:02:14 From: Anna Subject: Finding the area of a circle without using pi I need to find out how to find the area of a circle without using pi. I have to explain it and prove the answer. Please help. Date: 02/25/2001 at 13:17:55 From: Doctor Roy Subject: Re: Finding the area of a circle without using pi Hello, Thanks for writing to Dr. Math. There is a way, although it's really more of a cheat. Remember how pi is defined. It is the ratio of the circumference of a circle to its radius, or: pi = C/d Now the area of a circle is given by the following formula: A = pi*r^2 We can combine these two facts to get an expression that does not have pi in it. Of course pi will be involved, but it will be hidden in the interaction between circumference and diameter. I hope this helps. - Doctor Roy, The Math Forum http://mathforum.org/dr.math/ |
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