Question

If $A=\{x:x\in Nandx<20\}$ and
$B=\{x:x\in Nandx\le 5\}$ then write the set $A-B$ in the Set-Builder form.

Answer 1

From given $A$ and $B$,

Set-Builder form of $A-B$ is $\{x:xϵNand5<x<20\}$