I think, Erasmus, he means instead of specifying e>0.
The difference Bitupon is that logically, if you say "for every number" without specifying strictly greater than zero, the next bit would have to hold even for zero and negative epsilon values.
A more essential alternative is to use the definition of "open neighborhood" in topology but the disequalities give the same effect. High school calculus books use them because it is simpler, although topology gives a better overall view, once one has climbed the hill.
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Inutil insegnŕ al mus, si piart timp, in plui si infastiděs la bestie.
Hypography Forum PITA...... er, Administrator.
