1.3+2.32+3.33+4.34+….+n.3n=
A. (2n-1)3n+1+3/4
B. (2n+1)3n+1+3/4
C. (2n+1)3n+1-3/4
D. (2n-1)3n+1-3/4
Sum of n brackets of (1)+(1/3+1/32)+(1/33+1/34+1/35)+…. Is
A. (3n-1)3/2.4n-1
B. (3n-1)/2.3 (n-1)(n+2)/2
C. (3n+1)/3.7n-1
D. none
1.3.4+2.4.5+3.5.6+…. n terms
A. n(n+1)(n+2)/6
B. n(n+1)(3n2+23n+46)/12
C. n(27n3+90n2+45n-50)/4
D. n(n+1)(2n+1)/6
(1)+(2+3)+(4+5+6)+….n brackets=
A. n(n+1)(n2+n+2)/8
B. n(n+1)(n2-n+2)/8
C. n(n-1)(n2+n+2)/8
D. n(n-1)(n2-n+2)/8
1.22+2.32+3/42+….n(n+1)2/12.2+22.3+32.4+…n2(n+1)=
A. 3n+5/3n+1
B. 3n+1/3n+5
C. (3n+1)(3n+5)
D. none
The value of the sum in the n th bracket of (1)+(2+3)+(4+5+6+7)+(8+9+10+15)+… is
A. 2n(2n+2n-1-1)
B. 2n-1(2n+2n-1-1)
C. 2n-2(2n+2n-1-1)
D. none
(1)+(2+3+4)+(5+6+7+8+9)+… n brackets=
A. n(n+1)(n+2)/6
B. n2(n2+1)/2
C. n(n+1)(n+2)
D. n(n+1)(2n+1)/6
(14/1.3)+(24/3.5)+(34/5.7)+….+n4/(2n+1)(2n-1)=
A. n(n+1)(n+2)/6n
B. n(n+1)(n2+n+1)/6(2n+1)
C. n(n+2)(n+3)2
D. none
13+12+1+ 23+22+2+ 33+32+3+…3n terms=
A. n(n+1)2
B. n2(n-1)
C. n(n+1)(3n2+7n+8)/12
D. none
The equation of lines passing through the intersection of lines x-2y+5=0 and 3x+2y+7=0 and perpendicular to x-y=0 is
A. x + y = 0
B. x + y = 2
C. x + y + 2=0
D. x + y +1=0
(1)+(1+2)+(1+2+3)+…. n brackets=
A. n(n+1)(n+2)/6
B. n(n+1)(3n2+23n+46)/12
C. n(27n3+90n2+45n-50)/4
D. n(n+1)(2n+1)/6
The sum of the first n terms of the series 12+2.22+32+2.42+52+2.62+…. Is n(n+1)2/2 when n is even. When n is odd the sum is
A. 3n(n+1)/2
B. [n(n+1)/2]2
C. n(n+1)2/4
D. n2(n+1)/2
1.4.7+4.7.10+7.10.13+…. n terms
A. n(n+1)(n+2)/6
B. n(n+1)(3n2+23n+46)/12
C. n(27n3+90n2+45n-50)/4
D. n(n+1)(2n+1)/6
(12/3)+(12+22/5)+(12+22+32/7)+… n terms
A. n(n+1)(n+2)/18
B. n(n+1)(n+2)/6
C. n(n+1)(n+2)/3
D. 2n(n+1)(n+2)/3
(13/1)+(13+23/1+3)+(13+23+33/1+3+5)+….. n terms
A. n(2n2+9n+13)/24
B. n(2n3+9n+13)/18
C. n(n2+9n+13)/24
D. n(n2+9n+13)/8
2.12+3.22+4.32+….+(n+1)n2=
A. n(n+1)(n+2)(3n+5)/12
B. n(n+1)(n+2)(n+3)/4
C. 2n(n+1)(n+2)(n+3)
D. n(n+1)(n+2)(3n+1)/12