In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $x \in A$ and $A \in B,$ then $x \in B$
False
Let $A=\{1,2\}$ and $B=\{1,\{1,2\},\{3\}\}$
Now, $2 \in\{1,2\}$ and $\{1,2\}$ $\in\{\{3\}, 1,\{1,2\}\}$
$\therefore A \in B$
Howerer, $2 \notin\{\{3\}, 1,\{1,2\}\}$
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{1,2,5\}\subset A$
Which of the following pairs of sets are equal ? Justify your answer.
$\mathrm{X} ,$ the set of letters in $“\mathrm{ALLOY}"$ and $\mathrm{B} ,$ the set of letters in $“\mathrm{LOYAL}”.$
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 8\, .......\, A $
Set $A$ has $m$ elements and Set $B$ has $n$ elements. If the total number of subsets of $A$ is $112$ more than the total number of subsets of $B$, then the value of $m \times n$ is
Write the following sets in the set-builder form :
$\{ 3,6,9,12\}$