[tex]\lor[/tex] is the logical or/disjunction symbol. [tex]p\lor q[/tex] means "[tex]p[/tex] or [tex]q[/tex]". Disjunction is commutative, which means [tex]p\lor q[/tex] is equivalent to [tex]q\lor p[/tex].
So if [tex]p[/tex] represents [tex]x<-3[/tex] and [tex]q[/tex] represents [tex]x>3[/tex], then [tex]p\lor q\equiv q\lor p[/tex] means [tex]x>3[/tex] or [tex]x<-3[/tex].