" 5."1+(1+2)+(1+2+3)+(1+2+3+4)+...

What will come next in the series given below ? 1 1 2 1 2 3 1 2 3 4 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 6 1 2 3 4 5 6 7 1 2 3 4 5 1) 1 2) 5 3) 6 4) 2 5) None of these

(1) / (1.2) + (1.3) / (1.2.3.4) + (1.3.5) / (1.2.3.4.5.6) + .... oo

1+ (1) / (2) (. 3) / (5) (1.3) / (2.4) ((3) / (5)) ^ (2) + (1.3.5) / (2.4.6) ( (3) / (5)) ^ (3) + ........ oo =

Solve (a) 2/3 + 1/7 (b) 3/10 + 7/15 (c) 4/9 + 2/7 (d) 5/7 + 1/3 (e) 2/5 + 1/6 (f) 4/5 + 2/3 (g) (3/4) (1/3) (h) (5/6) (1/3) (1) 2/3 + 3/4 + 1/2 (1) 1/2 + 1/3 = 1/6 (k) (1) 1/3 + (3) 2/3 (1) (4) 2/3 +(3) 1/4 (m) ((16)/5))(7/5)

Solve (a) 2/3 + 1/7 (b) 3/10 + 7/15 (c) 4/9 + 2/7 (d) 5/7 + 1/3 (e) 2/5 + 1/6 (f) 4/5 + 2/3 (g) (3/4) (1/3) (h) (5/6) (1/3) (1) 2/3 + 3/4 + 1/2 (1) 1/2 + 1/3 = 1/6 (k) (1) 1/3 + (3) 2/3 (1) (4) 2/3 +(3) 1/4 (m) ((16)/5))(7/5)

If A= {1, 2, 3}, B= {3, 4} and C= {4, 5, 6}, then (A xx B) uu (A xx C) = {(1, 3), (1,4), (1,5), (1,6), (2,3), (2,4), (2,5), (2,6), (3,3), (3,4), (3,5),(3,6)}

1/(1.2)+(1.3)/(1.2.3.4)+(1.3.5)/(1.2.3.4.5.6)+.....oo

For the series, S=1+1/((1+3))(1+2)^2+1/((1+3+5))(1+2+3)^2+1/((1+3+5+7)) (1+2+3+4)^2 +...