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The value of sum(r=1)^(n)(nP(r))/(r!)=...

The value of `sum_(r=1)^(n)(nP_(r))/(r!)=`

A

`2^n`

B

`2^n-1`

C

`2^(n-1)`

D

`2^n+1`

Text Solution

Verified by Experts

The correct Answer is:
B
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