## Thomas' Calculus 13th Edition

The nth partial sums are: $s_n=(\sqrt 5 -\sqrt 4)+(\sqrt 6 -\sqrt 5)+.....[\sqrt {n+4} -\sqrt {n+3}]=(\sqrt{n+4}-2)$ Now, apply limits,we gwt $\lim\limits_{n \to \infty} s_n=\sqrt{n+4}-2=\infty$ This implies that when $s_n \to \infty$ as $n \to \infty$, thus, the g series is divergent.