Find the sum of the following series to infinity :
10 – 9 + 8.1 – 7.29 + …. ∞
We observe that the above progression possess a common ratio. So it is a geometric progression.
Common ratio = r =
Sum of infinite GP = ,where a is the first term and r is the common ratio.
Note: We can only use the above formula if |r|<1
Clearly, a = 10 and r =
⇒ sum =