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If n and r are two positive integers suc...

If n and r are two positive integers such that `nger,"then "^(n)C_(r-1)+""^(n)C_(r)=`

A

`""^(n)C_(n-r)`

B

`""^(n)C_(r)`

C

`""^(n-1)C_(r)`

D

`""^(n+1)C_(r)`

Text Solution

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The correct Answer is:
D
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