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Math → Functions

Function vs. Relation

What are you trying to remember?

How can you remember the difference between a function and a relation?

The Cue

FUNction → For every input, Unique output | Relation → Repeated inputs can have different outputs

Why it works

A function assigns exactly one output to each input. A relation is any set of ordered pairs and may assign different outputs to the same input. Every function is a relation, but not every relation is a function.

One-line recall

Function → One output per input · Relation → Multiple outputs allowed

Quick Check

Which relation is also a function?