Question

If $U=\{1,2,3,4,5\}$ and $A=\{2,4,5\}$ then find $A^{\prime }$.

Answer 1

$U=\{1,2,3,4,5\}$

$A=\{2,4,5\}$

$A^{\prime }=U-A$
$A^{\prime }=\{1,2,3,4,5\}-\{2,4,5\}$
$\therefore A^{\prime }=\{1,3\}$