Question

How many terms are there in 3,9,27,81........531441?

Answer 1

As we can see The squence is in G.p.
So, Here a=3, r=3.
So $a r^{n-1}=531441 \\ 3^n=531441 \\ 3^n= 3^{12} \\ n=12$
So, There are 12 terms in this G.P