Domain of the function $\frac{\sqrt{1 + x} - \sqrt{1 - x}}{x}$ is

If $U = \{2, 3, 4, 5, 6, 7, 8, 9, 10, 11\}$,$A = \{2, 4, 7\}$,$B = \{3, 5, 7, 9, 11\}$,and $C = \{7, 8, 9, 10, 11\}$,compute: $(A \cap U) \cap (B \cup C)$.

Consider the two sets:
$A = \{m \in R : \text{both the roots of } x^{2} - (m+1)x + m+4 = 0 \text{ are real}\}$ and $B = [-3, 5)$.
Which of the following is not true?

If $A = \{ 1, 2, 3, 4 \}$ and $B = \{ a, b \}$,and $f$ is a mapping such that $f: A \to B$,then the Cartesian product $A \times B$ is:

Let $Z$ be the set of integers. If $A = \{ x \in Z : 2^{(x + 2)(x^2 - 5x + 6)} = 1 \}$ and $B = \{ x \in Z : -3 < 2x - 1 < 9 \}$,then the number of subsets of the set $A \times B$ is:

If $A = \{x : x \text{ is a multiple of } 3\}$ and $B = \{x : x \text{ is a multiple of } 5\}$,then $A - B$ is ($\bar A$ denotes the complement of $A$).