From 12a08c18b8fdaeada77ab60fe2d8bc9b9c7afa65 Mon Sep 17 00:00:00 2001
From: Neel Parikh Definition: Permutation Rule A permutation is an ordered arrangement of n distinct objects. Those $n$ objects can
+ A permutation is an ordered arrangement of $n$ distinct objects. Those $n$ objects can
be permuted in $n \cdot (n – 1) \cdot (n – 2) \cdots 2 \cdot 1 = n!$ ways.Permutations of Distinct Objects
Definition: Combinations
-A combination is an unordered selection of r objects from a set of n objects. If all objects +
A combination is an unordered selection of $r$ objects from a set of $n$ objects. If all objects are distinct, and objects are not "replaced" once selected, then the number of ways of making the selection is:
$$