" 21) "1+(4)/(3)+(10)/(9)+(28)/(27)+...n" u varepsilon "EE" if "11=...

The sum of the series 1+(4)/(3)+(10)/(9)+(28)/(27)+.... upto n terms is

((4)/(9))^(2)-:((28)/(27))^(3)

(9/4)^4xx(28/27)^3

1/3,4/9,7/(27),(10)/(81),?,(16)/(729)

12(1)/(3)-(8)/(9)+(11)/(3)-4(11)/(9)=?

The sum of first n terms of the series (4)/(3),(10)/(9),(28)/(27),(82)/(81),(244)/(243),... is

The function u_(n) takes on the following values : u_(1) = ( 1)/( 4) , u_(2) = ( 1)/( 4) + ( 1)/( 10)"…....." u_(n) =(1)/( 3+1) + ( 1)/( 3^(2) + 1)+"…........." (1)/( 3^(n) + 1)"…........." Prove that underset( n rarr oo) ( "lim") u_(a) lt (1)/(2)

If (1)/(9!)+(1)/(10!)=(n)/(11!) , then n=121 .

If ( 10)^(9) + 2( 11)^(1) ( 10)^(8)+ 3 ( 11)^(2) ( 10)^(7)+"……….." + 10 ( 11)^(9)= k ( 10)^(9) , then k is equal to :