Surjective function

ID: surjective-function

Surjective function by Ciro Santilli 37 Updated 2025-07-16
Mnemonic: sur means over. So we are going over the codomain, and covering it entirely.
A surjective function, also known as a "onto" function, is a type of function in mathematics where every element in the codomain (the set of possible outputs) is mapped to by at least one element from the domain (the set of possible inputs).

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