If ${N_a} = [an:n \in N\} ,$ then ${N_5} \cap {N_7} = $
${N_7}$
$N$
${N_{35}}$
${N_5}$
Let $A$ and $B$ be subsets of a set $X$. Then
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
$A-B$
If $A$ and $B$ are two sets such that $A \subset B$, then what is $A \cup B ?$
Let $A = \{ (x,\,y):y = {e^x},\,x \in R\} $, $B = \{ (x,\,y):y = {e^{ - x}},\,x \in R\} .$ Then
If $A=\{1,2,3,4\}, B=\{3,4,5,6\}, C=\{5,6,7,8\}$ and $D=\{7,8,9,10\} ;$ find
$A \cup B$