R help - May 2009 - Newton's method for finding roots

Hey guys, i have a relatively simple problem.

I need to use netwon's method to find the root of a polynomial, lets say
x^3-2x-1

i start off with

p <- function(x) x^3-2*x-1

My method, which im sure is very amateur, is to type another function, which is
the derivative of p, and after picking an initial value to start off with, i
follow the steps of newton's method manually, but i dont think that is what
the question is asking.

I've done some research on wikipedia, but i cant seem to find any code that
will help me.

Can someone help?

Thanks a lot

_________________________________________________________________



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Kon Knafelman <konk2001 <at> hotmail.com> writes
> I need to use netwon's method to find the root of a polynomial, ..
It't time to get your homework date May 12 submitted.

http://markmail.org/message/x5vdbync3gxfs5hp

Dieter

"Search" on the left under "www.r-project.org" provide 5
different
search engines devoted to R.  The R-help archives for 4/20/2009 (+/-1 
depending on your local time zone and mine) contains an interesting 
discussion of this issue, Subj:  "Re: [R] Two or more dimensional root 
(Zero) finding". 


      Hope this helps. 
      Spencer

Kon Knafelman wrote:
> Hey guys, i have a relatively simple problem.
>
> I need to use netwon's method to find the root of a polynomial, lets
say x^3-2x-1
>
> i start off with
>
> p <- function(x) x^3-2*x-1
>
> My method, which im sure is very amateur, is to type another function,
which is the derivative of p, and after picking an initial value to start off
with, i follow the steps of newton's method manually, but i dont think that
is what the question is asking.
>
> I've done some research on wikipedia, but i cant seem to find any code
that will help me.
>
> Can someone help?
>
> Thanks a lot
>
> _________________________________________________________________
>
>
>
> 	[[alternative HTML version deleted]]
>
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