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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?