Functions · Example 3

Use the set of ordered pairs to determine whether the relation is a function.

(a) $\left\{\left(-3,27\right),\left(-2,8\right),\left(-1,1\right),\left(0,0\right),\left(1,1\right),\left(2,8\right),\left(3,27\right)\right\}$
(b) $\left\{\left(9,-3\right),\left(4,-2\right),\left(1,-1\right),\left(0,0\right),\left(1,1\right),\left(4,2\right),\left(9,3\right)\right\}$

OpenStax, Contemporary Mathematics · §5.7 Functions · Example 3