Find the sum of n terms of G.P where first term is a and common ratio is r.

if S_(n) denotes the sum of n terms of a G.P whose first term is a and common ratio is r then find the sum of S_(1),S_(3),S_(5).........,S_(2)n-1

Prove that the sum of n terms of GP with first term a and common ratio r is given by S_(n)=a(r^(n)-1)/(r-1)

Let S_n denote the sum of first n terms of a G.P. whose first term and common ratio are a and r respectively. On the basis of above information answer the following question: The sum of product of first n terms of the G.P. taken two at a time in (A) (r+1)/r S_nS_(n-1) (B) r/(r+1)S_n^2 (C) r/(r+1)S_nS_(n-1) (D) none of these

The sum of some terms of G.P.is 315 whose first term and the common ratio are 5 and 2, respectively.Find the last term and the number of terms.

The sum of some terms of a G.P.is 315 whose first term and the common ratio are and 2, respectively.Find the last term and the number of terms.

Prove that the nth term of the GP with first term a and common ratio r is given by a_(n)=ar^(n-1)

Sum to infinity of a GP is 15 and the sum to infinity of their squares is 45 .If a is the first term and r is the common ratio then the sum of the first 5 terms of the AP with first term a and common difference 3r is

If the sum of an infinite G.P. be 3 and the sum of the squares of its term is also 3, then its first term and common ratio are