Prove that: n! / r! x (n-r)! + n! / (r-1)! x (n-r+1) = (n+1)! / r! x – InterviewSolution

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Prove that: n! / r! x (n-r)! + n! / (r-1)! x (n-r+1) = (n+1)! / r! x (n-r+1)!

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Prove that:

n! / r! x (n-r)! + n! / (r-1)! x (n-r+1) = (n+1)! / r! x (n-r+1)!

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