What universal set $(s)$ would you propose for each of the following :
The set of right triangles
Write the following sets in the set-builder form :
$\{ 2,4,6 \ldots \} $
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{ \{ 3,4\} \} \subset A$
Which of the following are sets ? Justify your answer.
A team of eleven best-cricket batsmen of the world.
Write the solution set of the equation ${x^2} + x - 2 = 0$ in roster form.