Preparing for the math test, and cannot understand what to do for one of my practice problems:(adsbygoogle = window.adsbygoogle || []).push({});

I need to find if the series is convergent or divergent, using test for divergence (divergent if limit doesn't equal 0)

sigma from 1 to infinity of ln((n^2+1)/(2n^2+1))

I see that I should use l'Hopital rule, and show that as n goes to infinity, the limit will equal to 1/2 (and series is diverges), but the ln (ie, natural log) gives me a doubt about my answer...

Also, i figured that I can use one of the natural log properties and rewrite as sigma ln(n^2+1) - sigma ln(2n^2+1), but still i have no idea what to do with ln...

help! what kind of influence does the natural log have on this problem??

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# Convergent/divergent with natural log

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