Prove E(sigma)from r=0 to n, 3r nCr=4n Share with your friends Share 1 Shruti Tyagi answered this Dear Student, To Prove ∑r=0n3r×Crn=4nby binomial expansion a+bn=C0nanb0+C1nan-1b1....Cnna0bn= ∑r=0nCrn×an-r×brif we compare the two terms∑r=0n3r×Crn=∑r=0nCrn×an-r×brhence if we make a=1 and b=3we get ∑r=0nCrn×1n-r×3rwhich is same as given term, ∑r=0n3r×Crnputting the same values in a+bn=1+3n=4n Regards, 7 View Full Answer Akshat answered this Here's the answer 1 Arathy Venu answered this pls expets answer this in detail 1
