# Is the relation R ={(0,4), (1,5), (2,6), (2,7), (3,8)} a function?

Jun 15, 2015

No it is not a function.

#### Explanation:

A relation is a function is it does not have two pairs with the same first and different second elements.

Alternatively: A relation FAILS to be a function if it DOES have two such pairs.

The relation in this question includes $\left(2 , 6\right)$ and $\left(2 , 7\right)$, so it is not a function.