STATISTICS HELP!!?

👨🏻‍🏫 學術台數學

[匿名]

2016-03-14 2:12 am

nCr=nC(n-r) for all n and r smaller than or greater than n

回答 (3)

用戶57802

2016-03-14 2:15 am

definition of nCr is
nCr = n! / [r!(n-r)!]

👍 1 👎 0

用戶48836

2016-03-14 2:21 am

Prove that C(n,r) = C(n,n-r).

C(n,r) = n!/[(n-r)!r!] = n!/[r!(n-r)!]
= C(n,n-r)!]

Note that n-(n-r)=r.

👍 0 👎 1

Randy P

2016-03-14 2:15 am

Yes, that's true.

What's your question? What did you need help with?

👍 0 👎 1