" 67.Find the sum of first "n" terms of the series "1^(3)+3^(3)+5^(3)+...

Find the sum of first n terms of the series 1.3 + 2.5 + 3.7 + 4.9 +…..

The difference between the sum of the first k terms of the series 1^(3)+2^(3)+3^(3)+...+n^(3) and the sum of the first k terms of 1+2+3+....+n is 1980. The value of k is :

The difference between the sum of the first k terms of the series 1^(3)+2^(3)+3^(3)+...+n^(3) and the sum of the first k terms of 1+2+3+...+n is 1980. The value of k is

Find the sum to n terms of the series (1.2.3) + (2.3.4) + (3.4.5) ...

Find the sum of first n terms of the series whose nth term is 3n^(2)+5 .

Find the sum of the first n terms of the series 1/(sqrt(2) + sqrt(3)) + 1/(sqrt(3) + sqrt(4)) +...

Find the sum of first n terms of the following series : 1.2^(2) + 2.3^(2) + 3.4^(2)+…

Find the sum of n terms of the series 1. 2. 3+2. 3. 4+3. 4. 5+

Find the sum of n terms of the series 1. 2. 3+2. 3. 4+3. 4. 5+

Find the sum of the first n terms of the series 1^3+3.2^2+3^3+3.4^2+5^2+3.6^2+.... when n is odd