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If (N + 2)! = 60 [(N − 1)!], Find N. - Mathematics

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प्रश्न

If (n + 2)! = 60 [(n − 1)!], find n. 

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उत्तर

(n + 2)! = 60 [(n − 1)!]

\[\Rightarrow\](n + 2)\[\times\](n + 1)\[\times\](n)\[\times\]( 1)! = 60 [(n − 1)!]
\[\Rightarrow\](n + 2)\[\times\](n + 1)\[\times\](n) = 60
\[\Rightarrow\](n + 2)\[\times\](n + 1)\[\times\](n) = 5\[\times\]4\[\times\]3

∴ n = 3


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Factorial N (N!) Permutations and Combinations
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पाठ 16: Permutations - Exercise 16.1 [पृष्ठ ४]

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आरडी शर्मा Mathematics [English] Class 11
पाठ 16 Permutations
Exercise 16.1 | Q 7 | पृष्ठ ४

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