Question

Which of the following is the rule for the geometric
sequence 1, 3. 9. 27, ...?
an = 3.39-1
an = 3.31
an = 1.32
an = 1.39-1

Answer 1

Answer:

$a_{n}$ = 1 . $3^{n-1}$

Step-by-step explanation:

The n th term rule for a geometric sequence is

$a_{n}$ = a $r^{n-1}$

where a is the first term and r the common ratio

Here a = 1 and r = 3 ÷ 1 = 3 , thus

$a_{n}$ = 1 . $3^{n-1}$