If n is an odd positive integer, prove that the coefficients of the middle terms in the expansion of `(x+y)^n` are equal.

The coefficient of the middle term in the expansion of (x + 2y)^(6) is

Find the middle term in the expansion of (x+y)^(6) .

Find the middle terms in the expansion of (x+y)^(7) .

Find the middle terms in the expansion of (2x + y)^(7)

If n is a positive integer and r is a nonnegative integer, prove that the coefficients of x^r and x^(n-r) in the expansion of (1+x)^(n) are equal.

Find the middle terms in the expansions of (x/3 + 9Y)^10 .