Let $A, B,$ and $C$ be the sets such that $A \cup B=A \cup C$ and $A \cap B=A \cap C$. Show that $B = C$
Let, $A, B$ and $C$ be the sets such that $A \cup B=A \cup C$ and $A \cap B=A \cap C$.
To show: $B = C$
Let $x \in B$
$\Rightarrow x \in A \cup B \quad[B \subset A \cup B]$
$\Rightarrow x \in A \cup C \quad[A \cup B=A \cup C]$
$\Rightarrow x \in A$ or $x \in C$
Case $I$
Also, $x \in B$
$\therefore x \in A \cap B$
$\Rightarrow x \in A \cap C \quad[\because A \cap B=A \cap C]$
$\therefore x \in A$ and $x \in C$
$\therefore x \in C$
$\therefore B \subset C$
Similarly, we can show that $C \subset B$
$\therefore B=C$
Examine whether the following statements are true or false :
$\{ 1,2,3\} \subset \{ 1,3,5\} $
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 8\, .......\, A $
Consider the sets
$\phi, A=\{1,3\}, B=\{1,5,9\}, C=\{1,3,5,7,9\}$
Insert the symbol $\subset$ or $ \not\subset $ between each of the following pair of sets:
$A, \ldots B$
Are the following pair of sets equal ? Give reasons.
$A = \{ 2,3\} ,\quad \,\,\,B = \{ x:x$ is solution of ${x^2} + 5x + 6 = 0\} $
Examine whether the following statements are true or false :
$\{ a\} \in \{ a,b,c\} $