Question

Which of the following is 'not' a geometric sequence?

a. 1, 4, 16, 64, ...
b. 4, 2, 1, (1/2), ...
c. 3, 6, 12, 24, ...
d. 6, 4 (1/2), 3, 1 (1/2), ...

Answer 1

It’s b 3,6,9,12,14 because if you look it up it will give you the answer

Answer 2

d. 6, 4 (1/2), 3, 1 (1/2), ...

Explanation:

A geometric sequence is any sequence that is exponentially growing/decaying, so analyze the slopes. The slope for D is a constant -1.5, so it is a linear (not geometric) sequence.