\ \
The geometric sequence is
. \ \
Rewrite the sequence as
. \ \
The geometirc sequence is in the form of
. \ \
The first term of the sequence is
. \ \
Common ratio is
. \ \
Sum of the first
terms of the geometric series
. \ \
Where
is the first term and
is the common ratio. \ \
Substitute
and
in
. \ \
\ \
The sum of the first
terms of the series is
. \ \