Question

Find the sum of the geometric series.

8-2+1/2-1/8+....

Please select the best answer from the choices provided

A
B
C
D

Answer 1

`Sum=(32)/(5)=6.4`

Explanation:

we are given geometric series as

`8-2+(1)/(2)-(1)/(8)+.......`

we can use infinite sum formula

`sum=(a)/(1-r)`

where

a is first term

r is common ratio

so, we have

`a=8`

`r=(-2)/(8)`

`r=-(1)/(4)`

now, we can plug values

`sum=(8)/(1-(-(1)/(4)))`

`Sum=(32)/(5)=6.4`