If `n` and `r` are integers such that `1 < r < n` then `n . C (n-1, r-1) =`

n and r integers such that 1lerlen , then n. ""^(n-1)C_(r-1) is

If m,n,r are positive integers such that r lt m,n, then ""^(m)C_(r)+""^(m)C_(r-1)""^(n)C_(1)+""^(m)C_(r-2)""^(n)C_(2)+...+ ""^(m)C_(1)""^(n)C_(r-1)+""^(n)C_(r) equals

If m,n,r are positive integers such that r lt m,n, then ""^(m)C_(r)+""^(m)C_(r-1)""^(n)C_(1)+""^(m)C_(r-2)""^(n)C_(2)+...+ ""^(m)C_(1)""^(n)C_(r-1)+""^(n)C_(r) equals

If m,n,r are positive integers such that r lt m,n, then ""^(m)C_(r)+""^(m)C_(r-1)""^(n)C_(1)+""^(m)C_(r-2)""^(n)C_(2)+...+ ""^(m)C_(1)""^(n)C_(r-1)+""^(n)C_(r) equals

If m,n,r are positive integers such that rltm,n, then: ""^(m)C_(r)+""^(m)C_(r-1)""^(n)C_(1)+""^(m)C_(r-2)""^(n)C_(2)+ . . ..+""^(m)C_(1)""^(n)C_(r-1)+""^(n)C_(r) equals:

Let n and r be non negative integers such that 1<=r<=n* Then,^(n)C_(r)=(n)/(r)*^(n-1)C_(r-1)

Let n and r be no negative integers suych that r<=n. Then,^(n)C_(r)+^(n)C_(r-1)=^(n+1)C_(r)

If n and r are two positive integers such that nger,"then "^(n)C_(r-1)+""^(n)C_(r)=

Let n\ a n d\ r be non negative integers such that 1lt=rlt=ndot Then, \ ^n C_r=n/rdot\ \ ^(n-1)C_(r-1)\ dot