सिद्ध कीजिए कि - (i) `""^(8)P_(3) = ""^(7)P_(3) + 3. ""^(7)P_(2)`, (ii) `""^(9)P_(4) + 4.""^(9)P_(3) = ""^(10)P_(4)`

Explanation

(i) दायाँ पक्ष `= ""^(7)p_(3) + 3.""^(7)p_(2) = (7!)/(4!) + 3. (7!)/(5!) = (7!)/(4!) + 3.(7!)/(5.4!) = (7!)/(4!) (1+3/5)`
`= (7!)/(4!) (8/5) = (8.7!)/(5.4!) = (8!)/(5!) = (8!)/((8-3)!) = ""^(8)p_(3)` = बाँया पक्ष