(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

[tex]\sum_{n=1}^{\infty}\frac{1}{n^2}cosnx[/tex]

Apply the Weierstrass M-test to the series in order to find the domain of convergence.

2. Relevant equations

3. The attempt at a solution

Looking at the functions I think I have gottten to the following conclusion,

f1(x)=cosx <= 1

f2(x)=1/4 cos(2x) <= 1/4

I would pick my sequence to be 1/n^2. I am sure that 1/n^2 converges but does it work as a bound on each term? And then what should I do with these two (the series and the sequence of Mk.)?

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# Applying the Weierstrass M test

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