The sum of series ` 2[ 7^(-1)+3^(-1).7^(-3)+5^(-1).7^(-5)+...]` is

The sum of the series (1)/(1.3.5)+(1)/(3.5.7)+(1)/(5.7.9)+... is

The sum of the series (5)/(1.2.3)+(7)/(3.4.5)+(9)/(5.6.7)+.... is equal to

The sum of the series 5/(1. 2.3)+7/(3. 4.5)+9/(5. 6.7)+ ....is equal to

The sum of the infinite series is (1)/(1.3)+(1)/(3.5)+(1)/(5.7)+...oo(A)(1)/(7)(B)(1)/(3)(C)(1)/(5) (D) (1)/(2)

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