# epsilon delta

• Aug 9th 2008, 01:51 PM
Dubulus
epsilon delta
whats the deal with this wacky theorem? i learned it in class and had a mild understanding of it, but i don't see the use in defining a limit like that.
• Aug 9th 2008, 02:16 PM
o_O
It's not a wacky theorem. It's just a way of defining a limit. If you put some thought into it, the epsilon-delta definition of a limit makes a lot of sense.
• Aug 9th 2008, 02:35 PM
galactus
See here for a video on the subject.

YouTube - Calculus: Proof of a limit

I agree in that something that is rather intuitive is turned into a complicated sounding mess that can put new calc students off the subject.
• Aug 10th 2008, 02:21 AM
kalagota
Quote:

Originally Posted by Dubulus
whats the deal with this wacky theorem? i learned it in class and had a mild understanding of it, but i don't see the use in defining a limit like that.

very big.. especially when you are really into mathematics..

and.. you have been reading my service for yong on the other thread, right? :)
• Aug 10th 2008, 10:56 AM
Dubulus
i was just kiddin around with the wacky theorem remark...but once you've defined it in that respect, what do you do with it? i went through all my calculus courses and i never heard of it until my advanced mathematics class. so if im not using the definition to actually learn what it is, whats the point?
• Aug 11th 2008, 02:50 AM
kalagota
pointless.. and in fact, mathematicians are trying to work on spaces that will never exist such as \$\displaystyle \mathbb{R}^n\$ for \$\displaystyle n\geq4\$. and the question is, WHY?

...and, why do you stay as a math major knowing this situation?...

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anyways, since we are trying to study spaces (some of which never would exist), how would you explain that a "point" approaches another "point" along a function? for me, the easiest way to explain this is thru that epsilon-delta definition. since we were taught that this definition looks very much like our intuitive definition in one, two or three dimensional real-valued functions, it should be easily understood. (make sense? maybe..:) )

and if you asked me back why i stay as a math major, i'll answer "i just want to see and to appreciate the beauty of mathematics, aside from getting a degree and wanting to pass what i have learned, nothing so special.".... and i remember what my professors told us, "Learning mathematics(and when they say mathematics, they meant the broadest mathematics) should be a passion. If you only want money, you better shift out to another course."(i just want to share this..)