Which of the following are geometric series?

first is the geometric series

a geometric series is a sequence of numbers whose first term is non zero and each of the succeeding terms is equal to the Prcedding term multiply by a constant number.

if a = first term

and constant number = d

then

GP is given by

a,a r , a r^2 ,a r^3 and so on

in first

a = 1/2

and d = 1/2

and hence it is an GP

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