Which of the following is equivalent to nCr?(a) \(\frac{n!}{(n−r)! – InterviewSolution

InterviewSolution

1.	Which of the following is equivalent to nCr?(a) \(\frac{n!}{(n−r)!}\)(b) nCn-r(c) nCr-1(d) \(\frac{n_r+1}{r}\)
Answer» Correct option is (b) ⁿC_n-r

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