सिद्ध कीजिए कि
`(1)/(9!) + (1)/(10!) + (1)/(11!) = (122)/(11!)`

Explanation

बायाँ पक्ष `= 1/(9!) + (1)/(10!) + (1)/(11!) =(1)/(9!) + (1)/(10.9!) + (1)/(11.10.19!)`
`= 1/(9!) [1+1/10 + 1/(110)]`
`= 1/(9!) [(110 + 11 + 1)/(110)]`
`= (122)/(110(9!)) = (122)/(11.10.9!) = (122)/(11!) =` दायाँ पक्ष