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If x, y and r are positive integers , th...

If x, y and r are positive integers , then : `""^xC_r+""^rC_(r-1)""^yC_1+^xC_(r-2)""^yC_2+..........+""^yC_r` =

A

`(x!y!)/(r!)`

B

`((x+y)!)/(r!)`

C

`""^(x+y)C_r`

D

`""^(xy)C_r`

Text Solution

Verified by Experts

The correct Answer is:
C
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