Comment on Not that limit
etchinghillside@reddthat.com 1 day ago
It’s been a while… but isn’t that negative?
Or is there some default given of which side it’s approaching from.
SculptusPoe@lemmy.world 1 day ago
JustAPenguin@lemmy.world 1 day ago
I have a BA in Mathematics. The limit is indeed determined by the direction you approach the limiting value.
When given without specification, the limit is implied to come from the left, meaning it increases towards the limiting value, which is why you see +inf.
rooroo@feddit.org 1 day ago
Yeah but then it should be negative infinite, cause if x<8 the fraction is negative.
JustAPenguin@lemmy.world 1 day ago
Ah, I misread the - as a +. You’re correct! Sorry, I just woke up and am in the middle of my morning doomscrolling sesh
deadbeef79000@lemmy.nz 1 day ago
Conveniently modeled with the same limit.
Though I’m not sure what negative doom is and what happens when it approaches infinity.
carmo55@lemmy.zip 1 day 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.
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 11 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 1 day 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…
cows_are_underrated@feddit.org 1 day ago
Yeah, that’s my experience too. When we did this in school we always defined from which side we were approaching the function.
Ooops@feddit.org 1 day ago
It should be +/-∞
Minus or plus depending on the side from which you approach the limes.
Test_Tickles@lemmy.world 19 hours ago
LeFrog@discuss.tchncs.de 1 day ago
I think it is not defined. It has a limes from the left (- inf) and limes from the right (+ inf) but no two-sided limes.
dohpaz42@lemmy.world 1 day ago
Is that the Tootsie Roll Theorem?
abbadon420@sh.itjust.works 1 day ago
You put the lime on the coconut and drink it all up.
Peppycito@sh.itjust.works 1 day ago
You put the lime in the coconut. You’re such a good silly woman.
ch00f@lemmy.world 1 day ago
Yeah, it would have to be defined as a one-sided limit.