If the coefficients of `x^(9),x^(10),x^(11)` in expansion of `(1+x)^(n)` are in A.P., the prove that `n^(2)-41n+398=0`.

If the coefficients of 2^(nd), 3^(rd) and 4^(th) terms in expansion of (1+x)^n are in A.P then value of n is

If the coefficient of the rth, (r+1)th and (r+2)th terms in the expansion of (1+x)^(n) are in A.P., prove that n^(2) - n(4r +1) + 4r^(2) - 2=0 .

If the coefficients of 2nd, 3rd and 4th terms in the expansion of (1+x)^(2n) are in A.P. then

The coefficients of x^(p) and x^(q)(p,q in N) in the expansion of (1+x)^(p+q) are

If the coefficients of a^(r-1),\ a^r and \ a^(r+1) in the binomial expansion of (1+a)^n are in A.P., prove that n^2-n(4r+1)+4r^2-2=0.

The coefficients fo x^(n) in the expansion of (1+x)^(2n) and (1+x)^(2n-1) are in the ratio

The coefficient of x^(n) in the expansion of ((1 + x)/(1-x))^(2), is

The coefficient of x^(n) in the expansion of (1+x)(1-x)^(n) is

The coefficient of x^(n) in the expansion of log_(a)(1+x) is

If the coefficients of second, third and fourth terms in the expansion of (1 + x)^(2n) are in A.P., show that 2n^(2) - 9n + 7=0 .