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## #1 2018-01-06 08:08:56

Hannibal lecter
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Registered: 2016-02-11
Posts: 222
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### how to find root of f(x) = ln(x) by fixed point iteration?

Hi,

how to find root of f(x) =  - ln(x) by fixed point iteration?

Last edited by Hannibal lecter (2018-01-06 08:15:59)

Wisdom is a tree which grows in the heart and fruits on the tongue

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## #2 2018-01-06 21:01:43

bob bundy
Registered: 2010-06-20
Posts: 8,322

### Re: how to find root of f(x) = ln(x) by fixed point iteration?

hi Hannibal lecter

This should do it:

https://en.wikipedia.org/wiki/Newton%27s_method

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #3 2018-01-07 03:16:25

zetafunc
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Registered: 2014-05-21
Posts: 2,188
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### Re: how to find root of f(x) = ln(x) by fixed point iteration?

As bob points out, Newton-Raphson provides a pretty fast rate of convergence to the well-known root at
. In fact, after just 6 iterations, it has an error of around
.

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