Stage 32 · Counting, Permutations, Combinations & the Binomial Theorem

32.2.3 Factorials and Full Permutations

32.2 Permutations: When Order Counts Too

Point 3 of 6

32.2.3 Factorials and Full Permutations

Core idea

Line up all n in a row and multiply from n all the way down to 1, written n! — the fullest permutation there is

Module goal. Understand counting where the selection is ordered, master the permutation formula and factorials, and learn to spot permutation problems that carry restrictions
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