Home » Questions » Unexperienced [ Ask a new question ]

What term is 2916 in the geometric sequence 4,12,36, with solution

What term is 2916 in the geometric sequence 4,12,36, with solution

Asked by: Guest | Views: 39
Total answers/comments: 1
Guest [Entry]

"Solution

An = A1 ®^n-1

A1  = 1st term

r = 3

2916= 4(3)^n-1

2916/4 = 4/4 (3)^n-1, divide by 4

729 = 3^n-1, make 729 an exponent, becomes

3^6 = 3^(n-1), make exponent an equality since they have the same base, becomes

6= n-1

6+1 = n

n = 7

Answer: 7th term"