Q6 of 195 Page 16

Prove that: n! (n + 2) = n! + (n + 1)!

Given: n! (n + 2) = n! + (n + 1)!


R.H.S. = n! + (n + 1)!


= n! + (n + 1)(n + 1 – 1)!


= n! + (n + 1)n!


= n!(1 + n + 1)


= n! (n + 2) = L.H.S


L.H.S = R.H.S


Hence, Proved.


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