Question

Which of the following is an arithmetic sequence?
2.4.8. 16.
2.4.-6.8.
-8, -6,-4,-2

Answer 1

In the first case, notice that each term of the sequence is twice the previous element, then, this is not an arithmetic sequence

Also, on the third option, we have alternating signs (positive and negative), thus, this is not an arithmetic sequence.

Therefore, the only arithmetic sequence is: -8,-2,-4,-2,..., since we have that it has a common difference of 2.