Write the set $\{ x:x$ is a positive integer and ${x^2} < 40\} $ in the roster form.
The required numbers are $1,2,3,4,5,6 .$ So, the given set in the roster form is $\{1,2,3,4,5,6\}$
The number of elements in the set $\{ (a,\,b):2{a^2} + 3{b^2} = 35,\;a,\,b \in Z\} $, where $Z$ is the set of all integers, is
State whether each of the following set is finite or infinite :
The set of lines which are parallel to the $x\,-$ axis
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\varnothing \in A$
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:
$A, \ldots B$
Write the following sets in the set-builder form :
$\{ 3,6,9,12\}$
