If `a+1/((4a)/3+1/((4a)/3+.....oo))=5` then the value of `a^3/(72^3-a^6)=`

Let S denote sum of the series 3/(2^3)+4/(2^4 .3)+5/(2^6 .3)+6/(2^7 .5)+ ...... oo Then the value of S^(-1) is __________.

Let S denote sum of the series (3)/(2^(3))+(4)/(2^(4)*3)+(5)/(2^(6)*3)+(6)/(2^(7).5)+...oo Then the value of S^(-1) is

If a=1+(x^(3))/(3!)+(x^(6))/(6!)+......oo,b=x+(x^(4))/(4!)+(x^(7))/(7!)+......oo,c=(x^(2))/(2!)++(x^(5))/(5!)+(x^(8))/(8!)+ then the value of a^(3)+b^(3)+c^(3)-3abc.

Let S denote sum of the series 3/(2^3)+4/(2^4 .3)+5/(2^6 .3)+6/(2^7 .5)+oo Then the value of S^(-1) is __________.

Let S denote sum of the series 3/(2^3)+4/(2^4 .3)+5/(2^6 .3)+6/(2^7 .5)+oo Then the value of S^(-1) is __________.

1+3^2/(2!)+3^4/(4!)+3^6/(6!)+......oo is equal to

5(1)/(6)-3(1)/(4)+3(1)/(3)+4

Find the value of 3+1/(4+(1/(3+1/(4+1/(3+. . . oo))))) is equal to