Write the solution set of the equation ${x^2} + x - 2 = 0$ in roster form.
In the following state whether $\mathrm{A = B}$ or not :
$A = \{ x:x$ is a multiple of $10\} ;B = \{ 10,15,20,25,30 \ldots \ldots \} $
Make correct statements by filling in the symbols $\subset$ or $ \not\subset $ in the blank spaces:
$\{a, b, c\} \ldots\{b, c, d\}$
Which of the following is the empty set
Make correct statements by filling in the symbols $\subset$ or $ \not\subset $ in the blank spaces:
$\{ x:x$ is a student of class $\mathrm{XI}$ of your school $\} \ldots \{ x:x$ student of your school $\} $