First three terms in the expansion of `(x+a)^n` are respectivley 64, 576 and 2160. Find x,a and n.

The middle term in the expansion of (1 + x)^(2n) is :

Find the middle terms in the expansion of:- (x/3+9y)^10 .

Find the middle terms in the expansion of:- (3- x^3/6)^7

The first three terms in the expansion of a binomial are 1, 10 and 40. Find the expansion.

If the 2nd, 3rd and 4th terms in the expansion of (x+a)^n are 240, 720 and 1080 respectively, find x ,\ a ,\ ndot

The coefficients of the (r-1)^(th) , r^(th) and (r+1)^(th) terms in the expansion of (x + 1)^n are in the ratio 1:3:5. Find n and r.

Find the rth term from the end in the expansion of (x+a)^n .

The coefficients of three consecutive terms in the expansion of (1+a)^n are in the ratio : 6: 33: 110. Find n.

Find the middle terms in the expansion of : (x/y+y/x)^(2n+1) .