A. 4
B. 3
C. 12
D. 6
k.C0+k2.C1/2+K2. C2/3+.…………+kn+1.Cn/n+1 =
If x+y=1, then 2.nCrxr.yn-r =
2.C2+6.C3+12.C4+……….+n(n-1)Cn =
If the sum of the coefficients of (1+2x)n is 6561, then the greatest coefficient is
If (1+x+x2)n =Σr=02n rxr then a0+a2+a4+……….+a2n=