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NNTP-Posting-Date: Tue, 17 May 2011 08:17:53 -0500
Message-ID: <4DD27582.5DF9@mindspring.com>
Date: Tue, 17 May 2011 09:17:54 -0400
From: pete <pfiland@mindspring.com>
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Subject: Re: Fourth root of integer
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Charles Richmond wrote:
> 
> On 5/16/11 8:46 AM, pete wrote:
> > Old Wolf wrote:
> >>
> >> Looking for an algorithm to find the fourth root of
> >> a large integer (I have a multi-precision integer
> >> library already). If there is no exact fourth root then
> >> the floor or ceiling is OK, I don't need a 'remainder'
> >> or anything.
> >>
> >> Any ideas?
> >
> > Why not just the square root of the square root?
> >
> 
> The fourth root of (2143/22) gives PI to about 8 decimal places.
> (Using your hand calculator, take the square root twice.)

The line in the original post which mentions
"no exact fourth root then the floor or ceiling is OK", 
suugests that OP is talking about integer math.

However, according to my calculator
                       (2143/22) == 97.409090909090909090909090909091
            square root(2143/22) == 9.8696043947612666756665932864345
square root(square root(2143/22))== 3.141592652582646125206037179644

So, I guess that I don't see your point.

-- 
pete