Maths-
General
Easy

Question

If n and  are integers such that 1 less than straight r less than straight n then n c (n‐l, r‐l)=

  1. C(n,r)
  2. n C(n,r)
  3. rC(n,r)
  4. (n‐ 1) C(n,r)

The correct answer is: rC(n,r)


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