Asked by Anonymous
Find the first five terms of the sequence in which a1 = 6 and an = –3an – 1 – 12, if n ≥ 2.
Answers
Answered by
Reiny
It probably looked like this
a<sub>1</sub> = 6
a<sub>n</sub> = -3a<sub>n-1</sub> - 12 , n≥2
So ...
a<sub>1</sub> = 6
a<sub>2</sub> = -3a<sub>1</sub> - 12 = -3(6) - 12 = -30
a<sub>3</sub> = -3a<sub>2</sub> - 12 = -3(-30) - 12 = 78
carry on, only 2 more
a<sub>1</sub> = 6
a<sub>n</sub> = -3a<sub>n-1</sub> - 12 , n≥2
So ...
a<sub>1</sub> = 6
a<sub>2</sub> = -3a<sub>1</sub> - 12 = -3(6) - 12 = -30
a<sub>3</sub> = -3a<sub>2</sub> - 12 = -3(-30) - 12 = 78
carry on, only 2 more