Please check my answers:

For the following series, determine its convergence or divergence. If it converges, find its sum:

a) $\displaystyle \sum_{n=2}^{\infty} \frac{1}{n^2-1}$ converges to $\displaystyle 0$

b) $\displaystyle \sum_{n=1}^{\infty} \frac{n+1}{2n-1}$ diverges

c) $\displaystyle \sum_{n=2}^{\infty} \frac{n}{ln (n)}$ diverges

If some of the above are incorrect, could you please help me fix it?!