Combinatorics Flashcards
1
Q
What are combinations + formula
A
Order does not matter y 5C3 es 5×4/2! Or 10C7 es 10×9×8/3!
2
Q
Permutations que son y formula
A
Order matters (example) and you can use factorial if no subsets or nPk = n!/(n-k)!
3
Q
Which rule can we use for permutations of repeated items (example: ways to create 4 digit codes using DIIG)
A
Mississippi (n!/subset 1!× subset 2!…)
4
Q
Circular arrangements, number of ways to set n items in a circle
A
(N-1)!
5
Q
Permutations with restrictions
A
Superset! × total!
6
Q
Combinations with restrictions
A
Ctotal - Copuesta
7
Q
Independent counting method
A
Number of items 1 × number of items 2 (si es una constante utilizas powers)
