The common ratio in a geometric sequence is the ratio between 2 consecutive terms:
-8/2=-4,
then the sequence is 2, -8, 32, -128, -512, 2048, ...
let
be the nth term of the sequence, then
.
.
.
so clearly
and, clearly n are integers >0, since we have a 1st term, a second term and so on... of a sequence (we do not have a "zero'th term"!
Answer:
<span>C. an=2(-4)^n-1; all integers where n>0</span>
-8/2=-4,
then the sequence is 2, -8, 32, -128, -512, 2048, ...
let
.
.
.
so clearly
and, clearly n are integers >0, since we have a 1st term, a second term and so on... of a sequence (we do not have a "zero'th term"!
Answer:
<span>C. an=2(-4)^n-1; all integers where n>0</span>