# How to show venn diagram?

How to show the following sets by Venn diagrams?

Case 1: $$A=\{1,2,B\},B =\{3,4\}$$ Case 2: $$A=\{1,2,3,4\}, B=\{3,4\}$$

• Do you understand what a Venn diagram represents and how it works? Jun 29, 2015 at 10:11
• @Asaf..., yes.I edited my question.
– dimo
Jun 29, 2015 at 10:21

In case 1 the universe is $A=U_1=\{1,2,B\}$ and $B$ happens to be a set $\{3,4\}$. So, the "type" (whatever it means) of $B$ is the same as that of the "type" of $1$ and $2$. This means that $B\not \subset U_1$ but $B\in U_1$
In case 2 the universe is $A=U_2=\{1,2,3,4\}$. Now, the "type" of "B" is not the same as the type of $1,2,3,4$. Now, $B \subset U_2$ but $B \not \in U_2.$