Question

اذا كانت   A equals open curly brackets space 1 space comma space space 2 space comma space 3 space comma space 4 space close curly brackets space space space comma space space B equals open curly brackets space 3 space comma space 5 space close curly brackets  فان  B minus A equals
right to left empty set
open curly brackets space 1 space comma space space 2 space close curly brackets
open curly brackets space 5 space close curly brackets
open curly brackets space 1 space comma space space 2 space comma space space 4 space close curly brackets

Answer 1

{5}