[" 18.Find the sum to "n" terms of the series "],[qquad (1)/(1.3)+(1)/(3.5)+(1)/(5.7)+...]

Find the sum to n terms of the series: (1)/(1.3)+(1)/(3.5)+(1)/(5.7)+...

find the sum upto n terms of the series (1)/(1*3)+(1)/(3*5)+(1)/(5*7)+...

Find the sum to n terms of the series: 1/(1. 3)+1/(3. 5)+1/(5. 7)+

Find the sum to n terms of each of the following series : (1)/(1.3) + (1)/(3.5) + (1)/(5.7) +…

Find the sum to n terms of the series 1//(1xx3)+1//(3xx5)+1//(5xx7)+ cdots .

Find the sum to n terms of the series: 1+5+12+22+35+...

Find the sum of n terms of the series 1+(4)/(5)+(7)/(5^(2))+(10)/(5^(3))+

Find the sum to n terms of the series (1)/(1*3*5*7*9)+(1)/(3*5*7*9*11)+(1)/(5*7*9*11*13)+"......" . Also, find the sum to infinty terms.

Find the sum to n terms of the series (1)/(1*3*5*7*9)+(1)/(3*5*7*9*11)+(1)/(5*7*9*11*13)+"......" . Also, find the sum to infinty terms.