Question

What are the values of "a1" and "r" of the geometric series?

1 + 3 + 9 + 27 + 81

A.) a1 = 1 and r = 3
B.) a1 = 1 and r = $\frac{1}{3}$
C.) a1 = $\frac{1}{3}$ and r = 1
D.) a1 = 3 and r = 1

Answer 1

Answer:

But this one is an arithmetic series.

Answer 2

Step-by-step explanation:

a=first term=1

and

r=common ratio =tn+1/tn

r=3

Hence option A ) is the correct one