Question

Find the first five terms of the given recursively defined sequence.
an = 3an − 1 + 9 and a1 = 2

Answer 1

If yourexpression mean :

an = 3 a ( n − 1 ) + 9

a1 = 2

then

a2 = 3 a1 + 9 = 3 * 2 + 9 = 6 + 9 = 15

a3 = 3 a2 + 9 = 3 * 15 + 9 = 45 + 9 = 54

a4 = 3 a3 + 9 = 3 * 54 + 9 = 162 + 9 = 171

a5 = 3 a4 + 9 = 3 * 171 + 9 = 513 + 9 = 522