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Which of the following is incorrect?...

Which of the following is incorrect?

A

`^nC_r=^nC_(n-r)`

B

`^nC_r=^(n-1)C_r+^nC_(n-r)`

C

`^nC_r=^(n-1)C_r+^(n-1)C_(r-1)`

D

`r! ^nC_r=P_r`

Text Solution

Verified by Experts

The correct Answer is:
B
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