`(n!)/((n-r)!)` का मान निकालिए जब
(i) `n = 6, r = 2" "(ii) n = 9, r = 5`

Explanation

(i) ` :' n = 6 " और " r = 2`
` (lfloorn)/(lfloorn-r) = (lfloor6)/(lfloor6-2) = (lfloor6)/(lfloor4) = (6 xx 5 xx lfloor4)/(lfloor4) = 6 xx 5 = 30 `
अतः ` (lfloorn)/(lfloorn-r) = 30`
(ii) `:' n = 9` और r = 5
` (lfloorn)/(lfloorn-r) = (lfloor9)/(lfloor 9 - 5) = (lfloor 9)/(lfloor 4) `
` = ( 9 xx 8 xx 7 xx 6 xx 5 xx 4 xx 3 xx 2 xx 1)/( 4 xx 3 xx 2 xx 1) `
` = 9 xx 8 xx 7 xx 6 xx 5 = 15120`
अतः ` (lfloor n)/(lfloor n - r) = 15120`