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sum(r=0)^(n)(P(r))/(r!) is equal to...

`sum_(r=0)^(n)(P_(r))/(r!)` is equal to

A

`2^(n-1)`

B

`2^(n)`

C

`2^(n)+1`

D

`2^(n-1)`

Text Solution

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The correct Answer is:
B
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AAKASH SERIES-PERMUTATIONS & COMBINATIONS-EXERCISE-II
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