If the coefficients of `(r-5)^th` and `(2r - 1)^th` terms in the expansion of `(1 + x)^34` are equal, find r.

If the coefficients of rth and (r+1)t h terms in the expansion of (3+7x)^(29) are equal, then r equals a. 15 b. 21 c. 14 d. none of these

If the coefficients of the r^(th) term and the (r + 1)^(th) term in the expansion of (1 + x)^(20) are in the ratio 1:2 , then r is equal to

If the coefficients of the (2r+4)t h ,(r-2)t h term in the expansion of (1+x)^(18) are equal, then the value of r is.

r and n are positive integers r gt 1 , n gt 2 and coefficient of (r + 2)^(th) term and 3r^(th) term in the expansion of (1 + x)^(2n) are equal, then n equals

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

If the coefficients of r^(th),(r + 1)^(th) and (r + 2)^(th) terms in the binomial expansion of (1 + y)^(m) are in A.P., then m and r satisfy the equation

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

Find the 4^th term in the expansion of (x-2y)^12 .