Question

1. Which of the following is a geometric sequence?

5, -25, 125, -625,...
100,50, 0, -50,...
13,16,19, 22,...
2,4, 16,48,...

Answer 1

5, -25, 125, -625,...

Explanation:

In order to test if something is geometric, just divide each element by the previous element. It is geometric if the number is always the same.

-25/5=-5

125/-25=-5

-625/125=-5

The other options do not fall into this pattern.

Answer 2

5, -25, etc

Explanation:

It involves multiplying to get each answer, so it is geometric