Question

2. Consider the sequence –8, 4, -2, 1, -1/2, …
Answer the following questions about the sequence.
a) Is the sequence arithmetic or geometric? How do you know? Show all your work.


b) If the sequence is arithmetic, find the common difference, d. If the sequence is geometric, find the common ratio, r. Show all your work.

Answer 1

–8, 4, -2, 1, -1/2, …is geometric sequence since te ratio between each number & its precedent is equal to -1/2:

(-8) x (-1/2) = 4
(-2) x (-1/2) = 1 & so on and so forth