Answer:
Option (B)
Step-by-step explanation:
Given sequence is 45, 135, 405, 1215, 3645..........
Since it's a geometric sequence,
Common ratio of each successive term to the previous term
r = [tex]\frac{135}{45}=3[/tex]
First term of the sequence 'a' = 45
Explicit formula of a geometric sequence will be,
[tex]a_n=a(r)^{n-1}[/tex]
[tex]a_n=45(3)^{n-1}[/tex]
Recursive formula of this sequence will be,
[tex]a_n=3(a_{n-1})[/tex], [tex]a_1=45[/tex]
Therefore, Option (B) will be the answer.
