Attempt at a rigorous (dis)proof of uniform convergence

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end3r7
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Homework Statement


1) Test the following series for Uniform Convergence on [0,1]
[tex] \sum\limits_{n = 1}^{\inf } {\frac{{( - 1)^n }}{{n^{x}\ln (x)}}} [/tex]


Homework Equations





The Attempt at a Solution



Obviously, it's not uniformly convergent since f(n,1) = [tex] \sum\limits_{n = 1}^{\inf } {\frac{{( - 1)^n }}{{n\ln (1)}}} [/tex] is not continuous. I'm looking for a more rigorous proof though.

I'm wondering if thsi reasoning is correct:

What I did was show that I can get x arbitrarily close to 1, and since log(x) is continuous, I can get arbitrarily close 1. Basically, I showed that for any 'n', I can make [tex] log(x) < \frac{1}{ne} [/tex]
so for x sufficiently close to 1

[tex] |\frac{1}{{n^{x}\ln (x)}}| > \frac{1}{|{n||\ln (x)|}} > |\frac{ne}{n}| = e[/tex]

where first inequality holds because x is between 0 and 1.

Therefore the terms of the series do not go to zero uniformly on its domain, so it can't converge.

Is that a valid argument?
 
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The fact that the series is not even defined at 0 and 1 is enough to conlude that it does not converge (uniformly or not) on [0,1].

Are you sure the question asks you to discusss uniform converge on [0,1] and not (0,1) ??