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For 2le rlen,{:((n),(r)):}+2({:(n),(r-1)...

For `2le rlen,{:((n),(r)):}+2({:(n),(r-1):})({:(n),(r-2):})=`

A

`n+1 C_(r-1)`

B

`n+1 C_(r+1)`

C

`n+2 C_(r)`

D

`2 .n+2 C_(r)`

Text Solution

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The correct Answer is:
C
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