9514 1404 393
Answer:
geometric sequence
Step-by-step explanation:
The terms of the sequence have a common ratio of -12/3 = -4, so the sequence is geometric. The general term is ...
an = 3(-4)^(n-1)
so the sum can be written as ...
[tex]\displaystyle\sum_{n=0}^\infty3(-4)^n[/tex]
(Note the summation starts at n=0, corresponding to a first term of 3.)
