I'm a student, solving convergence problems today.
I can show that the series $\sum_{n=2}^\infty \frac{1}{n \ln{n}}$ diverges by integral test ($F(x) = \ln{(\ln{x})}, F'(x) = f(x) = \frac{1}{x \ln{x}}$)
But I don't have any idea for the convergence of $\sum_{n=2}^\infty \frac{(-1)^n}{n \ln(n)}$
any help would be appreciated.
Yes, this does converge. In alternating series', as long as the absolute value of the numbers get closer to zero, it converges. 1/ln(n)n always get closer to 0 as n gets closer to infinity.