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Article #411

Re: Roots of equations Was: Newton Raphsons iteration method

#411
From: Roger Alexander
Date: Thu, 03 Sep 1992 12:57
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In <SMITH.92Sep2103757@minerva.harvard.edu> smith@minerva.harvard.edu (Steven Smith) writes:

>alex@iastate.edu (Roger Alexander) writes:

>>          Not so.  The solutions of the equation are isolated (implicit
>> function theorem) but there may be infinitely many.  Let
>>
>>          g(x,y) = (exp(x)cos(y)-1, exp(x) sin(y)).
>>
>> Then det g' = exp(2x) != 0 anywhere, but g(0,2*Pi*n) = 0 for every
>> integer n.

>			[...]  The example x -> sin x works too.

This function is not an example because the derivative has a zero.
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From: alex@iastate.edu (Roger Alexander)
Subject: Re: Roots of equations Was: Newton Raphsons iteration method
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References: <1992Sep1.094300.2414@nuscc.nus.sg>  <SMITH.92Sep1154327@minerva.harvard.edu>  <alex.715433129@pv3448.vincent.iastate.edu> <SMITH.92Sep2103757@minerva.harvard.edu>
Date: Thu, 3 Sep 1992 12:57:15 GMT
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