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Permutations and Combinations (Metric)

Learn, or revise, permutations and combinations, an the binomial theorem.

Permutations and Combinations

The number of permutations of \(r\) objects from \(n\), and the number of choices of \(r\) objects from \(n\).

The expansion of \((a+b)^n\) for positive integer \(n\).