Question 446363
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Hi,
C(n,x) = {{{n!/(x!(n-x)!)}}} and P(n,x) = {{{n!/(n-x)!)}}}
1. P(4,4) = 24
2. C(4,4) = 4!/4!0! = 1   Note: 0! = 1
3. 5! = 5*4*3*2*1 = 120
4. C(7,4)= 7!/4!3! = 7*6*5*3*2/4*3*2*3*2 = 7*5 = 35
5. P^C(5,5)  C(5,5) = 1  P^1 = P 
6. 3!+ 0/2!*1! = 3! = 6