Question

(n+2)! / (n-1)! is divisible by An E N
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Answer 1

Step-by-step explanation:

Hint. Note that n2+1n+1=n2−1+2n+1=n−1+2n+

Answer 2

formula by which this sum can do => (a+b) (a-b) = a^2 - b^2.