The series is
.
Ratio Test :
\(i) If
, then the series is
is absolutely convergent.
(ii) If
or
, then the series is
is divergent.
(iii) If
, then the ratio test is inconclusive.
Here
and
.




.
.
Therefore, the series
is diverges by using ratio test.
The series
is diverges by using ratio test.