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

$A \cup C$

Consider the following relations :

$(1) \,\,\,A – B = A – (A \cap B)$

$(2) \,\,\,A = (A \cap B) \cup (A – B)$

$(3) \,\,\,A – (B \cup C) = (A – B) \cup (A – C)$

which of these is/are correct

Find the union of each of the following pairs of sets :

$A = \{ x:x$ is a natural number and $1\, < \,x\, \le \,6\} $

$B = \{ x:x$ is a natural number and $6\, < \,x\, < \,10\} $

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

$B \cup D$

Let $A$ and $B$ be subsets of a set $X$. Then