^(n)C_(r)=(n!)/(r!(n-r)!)quad " Erample "17" If "^(n)C_(9)=^(n)C_(8)," find "^(n)C_(17)

If ^(^^)nC_(9)=^(n)C_(8), find ^(n)C_(17)

"^(n)C_(r)=^(n)C_(n-r)

If .^(n)C_(r-1)=.^(n)C_(3r) , find r.

If ^n C_9=^n C_8, find ^nC_17

(i) If ""^(n)C_(8)= ""^(n)C_(2) , find ""^(n)C_(2) . (ii) If ""^(n)C_(10)= ""^(n)C_(12) , determine n and hence ""^(n)C_(5) . (iii) If ""^(n)C_(9)= ""^(n)C_(8) , find ""^(n)C_(17) .

If .^(n)P_(r)=840,.^(n)C_(r)=35, then find n=

If ""^(n)P_(r)=""^(n)P_((r+1)) and ""^(n)C_(r) = ""^(n)C_(r-1), then (n,r) =