Answer:
A. f(1)=9, f(n+1)=f(n)-4 for n> or equal to 1
Step-by-step explanation:
Given the sequence:
We can easily calculate the difference of terms:
As the difference of terms is same and equal to -4, it is the AP (arithmetic progression)
This sequence can be defined In the form of function as:
All the above matches the first answer choice: