Asked to test the following for convergence using the comparason test as much as possible.

1. 1/(n^p-n^q) 0<q<p I thin kthe limit in this one does not exist but cant say why.

2. sqrt(N^2+1) - n

3. (n^(1/n) -1) I think this converges to a limit of -1 but cant show why

Please help I am totally stuck.

Regards

Niall101