Let $\mathrm{U}$ be universal set of all the students of Class $\mathrm{XI}$ of a coeducational school and $\mathrm{A}$ be the set of all girls in Class $\mathrm{XI}$. Find $\mathrm{A}'.$
Since $A$ is the set of all girls, $A'$ is clearly the set of all boys in the class.
Now, we want to find the results for $(A \cup B)^{\prime}$ and $A^{\prime} \cap B^{\prime}$ in the followng example.
If $U=\{a, b, c, d, e, f, g, h\},$ find the complements of the following sets:
$A=\{a, b, c\}$
Taking the set of natural numbers as the universal set, write down the complements of the following sets:
$\{ x:x\, \ge \,7\} $
Draw appropriate Venn diagram for each of the following:
$A^{\prime} \cap B^{\prime}$
Taking the set of natural numbers as the universal set, write down the complements of the following sets:
$\{ x:x$ is a natural number divisible by $ 3 $ and $5\} $
Fill in the blanks to make each of the following a true statement :
$A \cup A^{\prime}=\ldots$