$\"\"$

The series is $\"\"$ .

Expand the series.

$\"\"$ .

Observe the series, the series is in geometric series.

The sum of the series is $\"\"$ .

Where $\"\"$ is the first term and $\"\"$ is common ratio.

The first term of the series is $\"\"$ .

The common ratio is $\"\"$ .

The sum of the series is $\"\"$ .

Therefore, $\"\"$ .

$\"\"$

$\"\"$ .