Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{1,2,5\}\subset A$
Write the following sets in the set-builder form :
${\rm{\{ 5,25,125,625\} }}$
State which of the following sets are finite or infinite :
$\{ x:x \in N$ and $2x - 1 = 0\} $
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 $B = C$
The number of non-empty subsets of the set $\{1, 2, 3, 4\}$ is