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Emilga
Riemann
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Location: NTNU

[tex]1 = 0.999...[/tex]

[tex]\lim_{n \to \infty} \sqrt[n]{a} = 0\,\,\,\,,\,der\,a\in (0,\,1)[/tex]

For meg virker det logisk at:

[tex]\lim_{n \to \infty} (0.999...)^n = 0[/tex] men det stemmer altså ikke, pga. [tex]0.999... \not\in (0,\,1)[/tex]?
Last edited by Emilga on 04/03-2009 19:59, edited 1 time in total.
espen180
Gauss
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[tex]1\approx \lim_{n\to\infty} \sum_{i=1}^n 0.9\cdot10^{-n}[/tex]

Jeg synes det der var et bra argument mot at [tex]1= \lim_{n\to\infty} \sum_{i=1}^n 0.9\cdot10^{-n}[/tex]. Noen som har et motargument?
Emilga
Riemann
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Ja.

[tex]\frac 19 = 0.111...[/tex]

[tex]9\cdot\frac 19 = 9 \cdot 0.111...[/tex]

[tex]\frac 99 = 1 = 0.999...[/tex]

(Forresten har du helt rett; 1 [symbol:ikke_lik] 0.0999...)
Markonan
Euclid
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Fiffig! :) Men kan man ikke bare si at

[tex]1-0.999\ldots > 0[/tex]

[tex]1>0.999\ldots[/tex]
An ant on the move does more than a dozing ox.
Lao Tzu
Gustav
Tyrann
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Emomilol wrote:[tex]1 = 0.999...[/tex]

[tex]\lim_{n \to \infty} \sqrt[n]{a} = 0\,\,\,\,,\,der\,a\in (0,\,1)[/tex]

For meg virker det logisk at:

[tex]\lim_{n \to \infty} \sqrt[n]{0.999...} = 0[/tex] men det stemmer altså ikke, pga. [tex]0.999... \not\in (0,\,1)[/tex]?
Skulle mene at

[tex]\lim_{n \to \infty} \sqrt[n]{a} = 1\,\,\,\,,\,for\,a>0[/tex]
Last edited by Gustav on 04/03-2009 19:40, edited 1 time in total.
Magnus
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0.999..... = 1
Gustav
Tyrann
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Magnus wrote:0.999..... = 1
Oj, min feil. Beklager.
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