I forgot the part where δ > 0 and ε > 0, so I think it would be written like this:
##\forall \, \delta \ > 0, \exists \, \varepsilon(\delta)\ > 0, : \,\vert \, f(x)-L\,\vert \, < \varepsilon(\delta) \Longrightarrow \, 0 < \vert \,x-a\,\vert \,< \delta \,##
L is the supposed limit.
lim (x ->...