Determine the number of terms in a GP., if t1 = 3, tn = 96 and Sn = 189.
t1 = 3 first term a =3
Let r be common ratio
3
32r - 1 = 63r - 63 31r = 62 r = 2
Now, n - 1 = 5 n = 6
Hence, the number of terms is 6.
Find the least value of n for which the sum 1 + 3 + 32+ ...... to n terms is greater than 7000.
The ratio of the sum of first three terms is to that of first 6 terms of a G.P. is 125 : 152. Find the common ratio.
If S1, S2 and S3 be respectively the sums of n, 2n and 3n terms of a GP., prove that S1 (S3 – S2) = (S2 – S1)2
Let S be the sum, P the product and R the sum of the reciprocals of n terms in a G.P. Prove that