Find the sum of `1/(1!(n-1)!)+1/(3!(n-3))+1/(5!(n-5))+ ,`

The sum of the series 1/(1!(n-1)!)+1/(3!(n-3)!)+1/(5!(n-5)!)+…..+1/((n-1)!1!) is = (A) 1/(n!2^n) (B) 2^n/n! (C) 2^(n-1)/n! (D) 1/(n!2^(n-1)

If n in N o* n is even,then (1)/(1.(n-1)!)+(1)/(3*(n-3)!)+(1)/(5*(n-5)!)+......+(1)/((n-1)!1!)

the value of sum(-1)^(n+1)(n)/(5^(n))

Find the sum of the following. (1-(1)/(n))+(1-(2)/(n))+(1-(3)/(n))+... up to n terms.

Find the sum of the series: (1)/((1xx3))+(1)/((3xx5))+(1)/((5xx7))+...+(1)/((2n-1)(2n+1))

Find the sum, (i) 4-(1)/(n)+4-(2)/(n)+4-(3)/(n) …………upto n terms (ii) 1+(-2)+(-5)+….+(-236) .

Find the sum: sum_(n=1)^(10){((1)/(2))^(n-1)+((1)/(5))^(n+1)}