15:02 (watch on YouTube, opens in a new tab)Combinatorics: Do You Really Know How to COUNT!? | Part 1 | TMUA (watch on YouTube, opens in a new tab)
Counting sounds simple, until you need to be certain you've counted everything exactly once. The core ideas behind combinatorics — the multiplication principle, permutations, combinations, and arrangements with repeated objects — and why the formulas work, when to use them, and when dividing out duplicates can go wrong. Two questions guide us throughout: have we counted every possibility, and have we counted anything more than once?
- Combinatorics
- Permutations
- Combinations
