Question

Find the sum of the geometric series with the following values a1=1; r=4; n=5

Answer 1

dati:

a1=1

r=4

n=5

s5=¿?

solving:

formulati:

`s_(n)=a_(1).(r^(n)-1)/(r-1) \\ \\ \\s_(5)=1.(4^(5)-1)/(4-1)\\ \\ \\s_(5)=1.(1024-1)/(3)\\ \\ \\s_(5)=1.(1023)/(3)\\ \\ \\s_(5)=341`

sum of the n = 5 terms is:

341

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