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Which of the following is not correct?...

Which of the following is not correct?

A

1)`nC_(r)=n-1C_(r)+n-1C_(r-1)`

B

2)`r!nC_(r)=nP_(r)`

C

3)`nC_(r)=n-1C_(r)+nC_(n-r)`

D

4)`nC_(r) = nC_(n-r)`

Text Solution

Verified by Experts

The correct Answer is:
C
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