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Question
Find the value of `(("n" + 3)!)/(("n" + 1)!)`
Solution
`(("n" + 3)!)/(("n" + 1)!) = (("n" + 3)("n" + 2)("n" + 1)!)/(("n" + 1)!)`
= (n + 3)(n + 2)
= n2 + 3n + 2n + 6
= n2 + 5n + 6
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