If the rth term in the expansion of `(1+x)^20` has its coefficient equal to that of the (r+ 4)th term, find r

If the coefficient of (r +1)^(th) term in the expansion of (1 +x)^(2n) be equal to that of (r + 3)^(th) term , then

In the expansion of (1+x)^(20) , the coefficient of the rth term is to that of the (r+1) th term is in ratio 1 : 2 . Find the value of r .

prove that the coefficient of the (r +1)th term in the expansion of (1+x)^(n) is equal to the sum of the coefficients of the rth and (r+1)th terms in the expansion of (1+x)^(n-1)

If in the expansion of (1 + x)^(20) , the coefficients of r^(th) and (r +4)^(th) terms are equal, then the value of r,is

If in the expansion of (1+x)^43 the coefficient of (2r+1) th term is equal to the coefficietn of (r+2) th term, find r.

In the binomial expansion of (1+x)^34 , the coefficients of the (2r-1)th and the (r-5)th terms are equal. Find r.

If the rth term is the middle term in the expansion of (x^(2)-(1)/(2x))^(20) , then the (r+3)th term is:

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