Re: I want!

On 27 Mar 2007 20:28:43 GMT, Bernard Peek <bap@xxxxxxxxxxxxxxxx>
wrote:

On 2007-03-27, Austin Shackles <austinDITCHTHISFORBETTERRESULTS@xxxxxxxxxxxx> wrote:

The one I've never learnt and must hunt is deriving square roots efficiently
on paper. I can do it by trial and error, but there's a more refined
technique.

Called the "Babylonian method" and it jbexes by trial and error. Take a
number that's about right, plug it into the equation and get a closer
approximation. Lather, rinse, repeat.

From Wikipedia:

1. Start with an arbitrary positive start value r (the closer to the
square root of x, the better).
2. Replace r by the average between r and x / r. (It is sufficient to
take an approximate value of the average, not too close to the previous
value of r and x / r in order to ensure convergence.)
3. Repeat steps 2 and 3.

Aha! ain't Google marvelous?

http://math.arizona.edu/~kerl/doc/square-root.html

That's the fella.

I goov- and it *is* only a goov- that it relies on

(n+(a/10))^2= (n^2) + (2*a*n/10) + (a^2)/100

I was taught it once, remeber it rarely, and use it yet more rarely
(OK, never in anger).
--
Mit der Dummheit kämpfen Götter selbst vergebens.
.

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