If `S=1+1/4+1/9+1/16+....` ,then `1+1/9+1/25+1/49....` equals (A) `S/2` (B) `(3S)/4` (C) `S- 1/4` (D) `S-1/2`

Cube of (-1)/2i s 1/8 (b) 1/(16) (c) -1/8 (d) (-1)/(16)

Cube of (-1)/2i s (a) 1/8 (b) 1/(16) (c) -1/8 (d) (-1)/(16)

If S=(1/2)^2+((1/2)^2 1)/3+((1/2)^3 1)/4+((1/2)^4 1)/5+...... ,t h e n (a) S=ln8-2 (b) S=ln(4/e) (c) S=ln4+1 (d) none of these

Two mutually perpendicular tangents of the parabola y^2=4a x meet the axis at P_1a n dP_2 . If S is the focus of the parabola, then 1/(S P_1) +1/(S P_2) is equal to 4/a (b) 2/1 (c) 1/a (d) 1/(4a)

1, 4, 9, 16, 20, 36, 49 (a) 1 (b) 9 (c) 20 (d) 49

S_(2n+1)-S_(2) must be equal to (A)((S_(1)-S_(2)))/(3)(1+(1)/(2^(2n-1)))

If S=1+4/3+9/9+(16)/(27)+oo, then find the value of [S] (where [.] is G.I.F.)

If S=1+4/3+9/9+(16)/(27)+oo, then find the value of [S] (where [.] is G.I.F.)

The parabola x^2=4y and y^2=4x divide the square region bounded by the lines x=4 , y=4 and the coordinate axes. If S_1, S_2, S_3 are respectively the areas of these parts numbered from top to bottom, then S_1 : S_2 : S_3 is (A) 2:1:2 (B) 1:2:1 (C) 1:2:3 (D) 1:1:1