Question

Find the common ratio of the geometric sequence: 1,−3,9,−27,81,…

A. 3
B. −13
C. -3
D. 13

Answer 1

-3

Explanation:

common ratio=a2/a1=-3/1=-3

2.

a1=3

a5=48

an=a1 r^(n-1)

48=3r^(5-1)

r^4=48/3=16=2^4

r=2

Answer 2

-3

Explanation: