Finding the limit of a piecewise function at an integer point

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Homework Statement


Evaluate the limits
lim x->2 f(x) if f(x) = 3, x an integer, or 1, otherwise.


Homework Equations





The Attempt at a Solution


I just 3 was the answer because I thought 2 is an integer and if x is an integer then the answer is 3. I was rather shocked to find that the answer is 1. I understand the definition of limits but I think I'm obviously mistaken about something. Thanks.
 
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appplejack said:

Homework Statement


Evaluate the limits
lim x->2 f(x) if f(x) = 3, x an integer, or 1, otherwise.

The Attempt at a Solution


I just 3 was the answer because I thought 2 is an integer and if x is an integer then the answer is 3. I was rather shocked to find that the answer is 1. I understand the definition of limits but I think I'm obviously mistaken about something. Thanks.
If you're shocked by that limit, then it's clear that you don't understand the definition of limits.
 
What is your intuitive understanding of what a limit is, appplejack?
 
lim x->c f(x)=L
as 'x' approaches c 'a number' from both sides (-,+) and F(x)= approaches L from both side (-,+).
 
Last edited:
appplejack said:
lim x->c f(x)=L
as 'x' approaches c 'a number' from both sides (-,+) and F(x)= approaches L from both side (-,+).

That's about right. But the definition of a limit doesn't say anything about the value of f(c) does it? It just talks about the value of f(x) where x is 'close to c'. Not equal to c.