MathLiveCombination formula
Counts the number of ways to choose k items from a set of n items when order does not matter. It is the standard formula for combinations in counting and probability.
\binom{n}{k} = \frac{n!}{k!\,(n-k)!} = \frac{n(n-1)\cdots(n-k+1)}{k(k-1)\cdots 1}What the symbols mean
| total number of items in the set | |
| number of items chosen from the set | |
| factorial of n, the product of all positive integers up to n |
About this formula
- FieldMathematics
- TopicCombinatorics
- LevelHigh school
- Also calledbinomial coefficient, n choose k, number of combinations, choose function, nCk, combinations without repetition
- SourceWikidata Q202805
Write it in Obsidian
MathLive is a free visual math editor for Obsidian. Run Find a formula, type “combination formula”, and it goes into your note as editable LaTeX. You can also scan formulas from screenshots, PDFs and handwriting.