$\"\"$

The series is $\"\"$ .

Consider $\"\"$ .

Hence $\"\"$ .

Substitute the corresponding values in $\"\"$ .

$\"\"$

If the value of $\"\"$ then $\"\"$ .

$\"\"$ .

The series is centered at $\"\"$ and the radius of convergence is $\"\"$ .

When the series is converges if $\"\"$ but the value of the series is never $\"\"$ .

Therefore, the series is converges only at $\"\"$ .

$\"\"$

The series is converges only at $\"\"$ .