1. Definition
Choosing m of n distinct elements without regard to order gives C(n,m)=n!/(m!(n−m)!).
3. Properties & Laws
- Unordered;
- Symmetric C(n,m)=C(n,n−m);
- C(n,0)=C(n,n)=1;
- P(n,m)=C(n,m)·m!.
4. Steps
- Enter n,m;
- Click "Calculate";
- Or click "Load Example".
5. Worked Examples
Example: C(5,3)=5!/(3!·2!)=10.
6. Common Pitfalls
Unordered;
Denominator includes m!;
Use symmetry.