The coefficient of x7 in (ax2-1/bx)11 is equal to the coefficient of x-7 in (ax-1/bx2) then ab=
The number of non zero terms in the expansion of (8+2)101 - (8-2)101 is
The coefficients of three consecutive terms in the expansion of (1+x)n are in the ratio 1:7:42, then n=
Which term of (2x-3y)12 when x=1, y=5/2 numerically greatest?
If two consecutive terms in the expansion of (x+a)n are equal where n is a positive integer then (n+1)a/x+a is