Question

Our teacher told us that we can find the sum of infinite terms in GP. How? It is infinity, which is endless. Then how can we find. ???

Answer 1

yes u r right but the formula that is given by teachers is applicable only if r of the gp is less than 1 and graeter than minus 1 therefore the term at the last( near to infinity ) will be 0.000000something or much less and it is negligible and the formula becomes

Answer 2

Hey !!

Thanks for such a beautiful question

Your teacher is correct, YES , We can find the sum of infinite terms of G.P. BUT given the condition that "Common difference" or r lies between 1 and 0
I.e. 0<r<1

We can find the sum of infinite terms of such G.P. because every second term keeps getting smaller ,and soon becomes negligible .

To find Sum of infinite terms of a G.P. with first term 'a' and common difference 'r' [where 0<r<1]

S∞ = a/(1-r)

Hope it helps you ^_^