Answer:
an= -3 an + 9 a
Step-by-step explanation:
The first value in series is 6 a.
When we put n=1 in equation an=-3 a(1) +9 a
=6 a
The second term is having value of 3 a in the series.
When we put n=2 in equation an=-3 a(2) +9 a
=3 a
And so on,
So, an=-3 an +9 a