$\{ X \}$ is fractional part of $X$.
$[ X ]$ is greatest integer function (integral part of $X$)
$| X |$ is modulus of $X$
1) $X^2 > \{ X \}$
2) $X^2 > [ X ]$
3) $X^2 ≥ 4$
4) $X^2 > | X |$
5) $[ X ] ≤ | X |$
Also can somebody please explain with the graph, it would become much easier to understand.
Regards