1 What is the fifth term in the geometric series whose initial term is 128 and common ratio is 1/2

A geometric series is the sum of an unlimited number of terms with a fixed ratio between them.

If denote first term and common ratio respectively, then the term is given by

Put

Put

Put

Therefore,

So, the fifth term is

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a(5)=8

Step-by-step explanation:

it is geometric  so we will use this equation:

a(n)=a1*(r)^(n-1)

and we have a(1)=128 , r=1/2    

So a(n)=128*(1/2)^(n-1)

fifth term : a(5)=128*(1/2)^(5-1)=8

hope this helps

i believe the answer is c.