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Is it possible to have $$\lim_{x\to 1} f(x)=-23$$ and $f(1)=107$? I just don't know how to explain this and I don't even know if the above situation is possible. Please help me.

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    Yes, if $f$ is not continuous you can construct those situations.2017-02-03
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    Can u please be a bit more clear?2017-02-03
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    Define a function $f$ that is constant $f(x)=-23$ for $x < 1$ and $f(1)=107$. Then the left-sided limit of $f$ when $x$ approaches $1$ is $-23$ but its value is $107$ at $x=1$.2017-02-03
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    Ok I got it. Thank you.2017-02-03
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    You're welcome.2017-02-03

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The answer is yes.

The most simple function like that is:

$$f(x)=-23\quad \text{for $x\ne 1$ and } f(1)=107$$

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    So it's possible!!2017-02-03
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    Yes, it is! There is a plenty of functions!2017-02-03
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    Nice! But I have another doubt. If lim x->-17 f(x)=20, is it possible to determine f(-17)?2017-02-03
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    If you have just that condition then NO. You must have some other condition about $f$. The above answer cans help. I can define $f(1)$ as I want, for example it could be $f(1)=0$ instead of $107$.2017-02-03
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    It's only the condition that I have specified in the above comment2017-02-03
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    So, the answer is NO.2017-02-03
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    Oh good! So the reason is that sufficient properties of f are not mentioned, right?2017-02-03
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    That is correct!2017-02-03
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    Great! Thanks a lot man!2017-02-03
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    You are very welcome!2017-02-03
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    Of course not! ^_^2017-02-03