Question

Find the formula for the geometric sequence 1, 5, 25, 125,...OA4, = 5-1OB. 0,= 5.50-1OC. a, = (-2)"-1D. 0,= -2"-1Reset Selection

Answer 1

Given: geometric series 1 , 5, 25 , 125,.................

Find: formula for the geometric series

Explanation: the general formula for the series is

$\begin{gathered} ar^{n-1} \\ 1.5^{n-1} \\ 5^{n-1} \end{gathered}$

Final answer:

$a_n=5^{n-1}$