• carmo55@lemmy.zip
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    18 hours ago

    This is just not true. The normal limit we have here means a limit would have to exist from both directions and they should be equal. They’re not, so the limit doesn’t exist.

    One-sided limits would be denoted by x -> 5– and x -> 5+ or similar.

    PS: in complex analysis, there is no distinction between +infty and -infty, so there it would be correct to say the function has limit infty at 5.

    • JustAPenguin@lemmy.world
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      2 hours ago

      You’re right. But in this case, which is the case I was referring to, there is no two sided limit. It is discontinuous. It is in this case which I was referring to. Sorry for not being clear.

    • Ephera@lemmy.ml
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      17 hours ago

      In my experience with maths, there’s a whole bunch of different conventions all over the place, so it might’ve genuinely been how they were taught, even if you were taught differently…

      • da_cow (she/her)@feddit.org
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        16 hours ago

        Yeah, that’s my experience too. When we did this in school we always defined from which side we were approaching the function.