HARD
JEE Main/Advance
IMPORTANT
Earn 100

Let S denotes the infinite sum 2+5x+9x2+14x3+20x4+ where |x|<1. Then S equals -

50% studentsanswered this correctly

Important Questions on Sequences and Series

HARD
JEE Main/Advance
IMPORTANT
The coefficient of x101 in the expansion of (1-x)(1-2x)1-22x1-2101x is -
HARD
JEE Main/Advance
IMPORTANT
The sum of the series 12+1+22+2+32+3++n2+n is equal to
HARD
JEE Main/Advance
IMPORTANT
The sum of the series 3+7+13+21+31+ to n terms is equal to
HARD
JEE Main/Advance
IMPORTANT
The sum of the series 712·62+1762·112+27112·162+... is
HARD
JEE Main/Advance
IMPORTANT
The sum to 100 terms of the series  1.2.3. +2.3.4.+3.4.5.++n(n+1)(n+2)+ is integral multiple of -
HARD
JEE Main/Advance
IMPORTANT
The sum of the first n terms of the series 12+2.22+32+2.42+.. is n(n+1)22 when n is even. Then the sum if n is odd, is
HARD
JEE Main/Advance
IMPORTANT
If x, y, z and w are non-zero real numbers and x2+5y2+5z2+4w2-4xy-4yz-4zw=0, then x, y, z, w are in
MEDIUM
JEE Main/Advance
IMPORTANT
n=0(lnx)nn! is equal to