Coupon Accepted Successfully!



I.   a, ar, ar2, ar3, ….. is a G.P.

First Term = a.

Common Ratio = r

In this G.P., we have –

(i)  an = arn – 1

(ii)        Sn =


        =  when r > 1

(iii)   Sum of an infinite G.P. =




It is Convenient to take

(i) three numbers in G.P. as , a, ar

(ii)    Four numbers in G.P. as ,, ar, ar2

(iii)   Five numbers in G.P. as , , a, ar, ar2




III.            Geometric mean between a and b is given by –

G.M. = .



IV.              If a, a1, a2, …, an, b are in G.P., then a1, a2, a3, ……, an are called the n geometric means between a and b.


Test Your Skills Now!
Take a Quiz now
Reviewer Name