Learn all the geometric progression formulas which help in solving sequence and series chapter problems. In sequence and series chapter after arithmetic progression formulas, the next important formulas are geometric progression formulas.
There are only four important formulas are there in geometric progression. If you learn these four formulas it is enough to solve any kind of problem-based on geometric progression (G.P).
List of important geometric progression formulas are given below:
The Formula for nth term in the geometric progression (G.P):
Where “a “is the first term in the geometric progression (G.P)
“r “ is a common ratio of G.P. It can find out by second term/first term or third term/second term and so on.
By using this nth term formula we can find any term in a geometric progression (G.P). But we should have known the values of “a” and “r “.
Finding the nth term from ending of the geometric progression is :
Where “l “is the last term in geometric progression (G.P)
“r “ means common ratio in the G.P.
From ending if you want to find any term like a 3rd term from ending or 7th term from ending then you can the above formula.
Sum of n terms of geometric progression:
Before finding sum of n terms of a G.P first we need to find common ratio i.e. r value.
After that, according to the r value, we can choose the appropriate formula.
Sum of infinite terms of G.P is :
So these are some important formulas in Geometric Progression. All these geometric progression formulas you have to learn without leaving any formula.
If you find any difficulty in remembering these formulas then write 5 to 6 times and learn these formulas. Still, if you need any other formulas on geometric progression let me know.