If two sets $A$ and $B$ are having $99$ elements in common, then the number of elements common to each of the sets $A \times B$ and $B \times A$ are
If $R$ is the set of all real numbers, what do the cartesian products $R \times R$ and $R \times R \times R$ represent?
If the set $A$ has $3$ elements and the set $B=\{3,4,5\},$ then find the number of elements in $( A \times B ).$
If $A$ and $B$ are two sets, then $A × B = B × A$ iff
$A = \{1, 2, 3\}$ and $B = \{3, 8\}$, then $(A \cup B) × (A \cap B)$ is