Is there any different between function and relation

 A function is a special kind of relation.
 Relations pair up x and y coordinates, either by listing them or by writing an equation.
Functions have the additional property that no two values of y have the same value of x. 

Yes. In a relation the numbers have a relationship though the use of a domain and range. In a function,there is a specific set of numbers and you would only get one range. All functions are relations but not all relations are functions.

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