If $A=\{1,2,3,4\},B=\{1,2,3,5,6\}$, then find

(i) $A\cap B$, (ii) $B\cap A$, (iii) $A-B$, (iv) $B-A$.

What do you observe?

Q. If $A=\{1,2,3,4\},B=\{3,4,5,6\},C=\{5,6,7,8\}$ and $D=\{7,8,9,10\}$; find
(i) $A\cup B$

Q. If $U=\{1,2,3,4,5,6,7,8,9,10\}$
$A=\{1,2,6,7\}$
$B=\{3,4,5,1\}$
$C=\{6,7,8,4\}$
Find
(i)${\left(A\cup B\right)}^{\prime }\cap {\left(A\cup C\right)}^{\prime }$
(ii)$(C^{\prime }-A)-\left(A-C\right)$
(iii)$\left(B\cap C\right)\cup \left(A\cap C\right)$
(iv)${\left(A\cup B\cup C\right)}^{\prime }$

Q. If $A=4,6,7,8,9,B=2,4,6$ and $C=1,2,3,4,5,6$, then find
(i) $A\cup (B\cap C)$ (ii) $A\cap (B\cup C)$ (iii) $A\setminus (C\setminus B)$

Q. From the given Venn diagram find
(i) $A$
(ii) $B$
(iii) $A\cup B$
(iv) $A\cap B$
Also verify that $n(A\cup B)=n\left(A\right)+n\left(B\right)-n(A\cap B)$

Q. If $A=\{3,6,9,12,15,18,21\};B=\{4,8,12,16,20\}$
$C=\{2,4,6,8,10,12,14,16\};D=\{5,10,15,20\}$; find
(i) $A-B$ (ii) $B-A$ (iii) $C-A$ (iv) $D-A$
(v) $B-C$ (vi) $B-D$ (vii) $C-B$ (viii) $D-B$