f:A B | The function f maps A to B |
| f(a) = b | where a A and bB |
Let A and B be sets. A function f from A to B is an assignment of exactly one element of B to each element of A.
We use several types of notation for functions:
| f:AB | The function f maps A to B |
| f(a) = b | where aA and bB |