A geometric sequence is defined recursively by a_n = 6a_(n -1)an=6an1. The first term of the sequence is 0.75. Which of the following is the explicit formula for the nth term of the sequence?

1 Answer
Dec 23, 2016

a_n = 0.75 xx (6)^(n-1)an=0.75×(6)n1

Explanation:

Given a_n = 0.75an=0.75

a_n = 6a_(n - 1)an=6an1

=> (a_n)/(a_(n-1) anan1 = 6

=> r = 6r=6

Now for geometric sequences, we know:

a_n = a_1 xx (r)^(n-1)an=a1×(r)n1

=> a_n = 0.75 xx (6)^(n-1)an=0.75×(6)n1