Which of the following are sets ? Justify your answer.
The collection of ten most talented writers of India.
The collection of ten most talented writer of India is not a well-defined collection because the criteria for determining a writer's talent vary from person to person.
Hence, this collection is not a set.
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{1,2,3\}\subset A$
Write the following intervals in set-builder form :
$\left[ {6,12} \right]$
State which of the following sets are finite or infinite :
$\{ x:x \in N$ and $x$ is odd $\} $
Consider the sets
$\phi, A=\{1,3\}, B=\{1,5,9\}, C=\{1,3,5,7,9\}$
Insert the symbol $\subset$ or $ \not\subset $ between each of the following pair of sets:
$\phi \,....\,B$
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{ \{ 3,4\} \} \subset A$