Question

Consider the sequence -2, 6, -18, 54,

Answer 1

Answer: The sequence is geometric

Step-by-step explanation:

In an arithmetic sequence, the consecutive terms differ by a common difference and this difference is linear.

Common difference = given term - the term before it

In geometric progression, the consecutive terms differ by a common ratio this difference is exponential.

Common ratio = given term/the term before it

Looking at the given sequence,

1) d = 6 - - 2 is not equal to - 18 - 6

Therefore, it is not an arithmetic sequence

2) r = 6/- 2 = - 18/6 = - 3

Therefore, it is a geometric sequence.