$\"\"$ \ \

The series $\"\"$ . \ \

Divergence test: \ \

For the series $\"\"$ , If $\"\"$ , then the series $\"\"$ is divergent. \ \

Here $\"\"$ . \ \

Find $\"\"$ . \ \

$\"\"$

$\"\"$ \ \

Since $\"\"$ is harmonic series, the series is divergent.

Since $\"\"$ is geometric series with $\"\"$ , series is convergent. \ \

The sum of a convergent series and divergent series is divergent. \ \

Therefore, the series $\"\"$ is divergent. $\"\"$ \ \

The series is divergent.