Prove that (n + 2) × (n!) + (n + 1) ! = (n!). (2n + 3)
To Prove :
Formula :
L.H.S. = (n + 2) × (n!) + (n + 1)!
= (n + 2) × (n!) + (n + 1) × (n!)
= (n!) × [(n + 2) + (n + 1)]
= (n!) × (2n + 3)
= R.H.S.
∴L.H.S. = R.H.S.
Conclusion : (n + 2) × (n!) + (n + 1)! = (n!) × (2n + 3)