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
The smallest set $A$ such that $A \cup \{1, 2\} = \{1, 2, 3, 5, 9\}$ is
In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $x \in A$ and $A \not\subset B$, then $x \in B$
State which of the following sets are finite or infinite :
$\{ x:x \in N$ and $x$ is prime $\} $