Question

Which of the following relations are functions from A = { 1, 4, 9, 16 } to B = { -1, 2, -3, -4, 5, 6 }. In case of a function, write down its range.

$f_2$ = { (1, -4), (1, -1), (9, -3), (16, 2) }.

Answer 1

Since element $1$ in set $A$ have two images in $B$ therfore $f_2$ is not a function.