# Thread: Help proving that an infinite series diverges

1. ## Help proving that an infinite series diverges

Show that diverges. Obtain a formula for Sn.

I'm not sure how to do this. This problem is in one of the first sections of my book on infinite series, so it probably should not involve much more than the geometric series or nth test for divergence.

2. Hi

Hint : $\ln\left( \frac{k}{k+1} \right) = \ln k - \ln (k+1)$. (write the first terms of the sum to see what happens)

3. Ah, I see now. Thanks.