surjective
- adjective
- /sɜrˈdʒɛktɪv/
- Specialized
- To determine if the function is surjective, we need to check that all possible outputs are achieved by some input.
Examples
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We're going to use the definition to do some proofs to prove that functions are surjective or onto.
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OK, now we have to show that it's surjective, that it's on to.
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In mathematics, a function is called surjective if every element in the output set corresponds to at least one element from the input set.
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A function can be classified as surjective when it covers the entire target set, meaning every element is mapped from the domain.
Synonyms
A function where every result comes from some input
Compounds
Surface Forms
Morphology
surjective = surject (opaque) = sur + ject + ive
Formed from the combining elements 'sur-' + 'ject' + '-ive', which are non‑productive and mathematically specialized, so the meaning is not recoverable for average learners from the parts.
Etymology
Surjective comes from two parts: sur- meaning 'over' and -ject meaning 'throw', the same root you see in project and inject. So a surjective function is like 'throwing' values 'over' the whole target set so that every item in the target is reached by at least one source value.