• MoffKalast@lemmy.world
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      4 hours ago

      The most realistic part of this joke is that the bartender is also a mathematician, probably after they did not qualify for any phd research grant.

  • rumba@lemmy.zip
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    9 hours ago

    And that -1/12 bs is why I cannot math.

    1+2+3 … tends toward infinity and there’s no amount of playing with numbers will convince me otherwise.

    • bort@sopuli.xyz
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      8 hours ago

      And that -1/12 bs is why I cannot math.

      it’s not actually math. It’s people coming up with alternative definitions and then feeling smug when their alternative definitions give weird results.

    • Maturin [any]@hexbear.net
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      8 hours ago

      1+2+3… absolutely diverges to infinity. In order to get the -1/12 result you have to explicitly suspend the normal rules governing math in very specific ways. Some YouTubers for clickbait effect pretend that you are not suspending the rules to get that result. However, suspending the rules in the ways that allow for -1/12 demonstrates all these patterns that are also cool if you are a big enough nerd to think number manipulation like that is cool.

    • TwilightKiddy@programming.dev
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      7 hours ago

      Hello, I play with numbers:

      1+2+3+...=S
      S-S=1+2+3+4+...
           -1-2-3-...=
      1+1+1+1+...=S-S=0
      

      Moral of the story: ones together are nothing.

      Thank you for your attention.

      • rumba@lemmy.zip
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        6 hours ago

        let me hand you a tissue, looks like you got some ‘stuff’ in your text box

      • jaybone@lemmy.zip
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        5 hours ago

        lol 1-1, 2-2 etc.

        How do you get 1 + 2-1?

        You need to distribute that minus sign to all numbers in the sequence. You can’t leave off the first one.

        • TwilightKiddy@programming.dev
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          4 hours ago

          It’s an infinite series, love, I just moved it, there are still enough elements in them because, well, they are infinite. If you are so sad about it, write the second one as 0-S, changes nothing but now you have a donut to pair up with the 1 in the first series.

        • prime_number_314159@lemmy.world
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          4 hours ago

          He has a plus one, and a minus one, a plus two, and a minus two, and so on. This is analogous to how conditionally convergent series can be modified to give any finite (or infinite) sum merely by changing the order of the terms.

  • crwth@piefed.zip
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    8 hours ago

    I had a student tasked with summing a finite geometric sequence with |r|>1, let’s say 1+2+4+8+16. He had apparently forgotten the formula for that, but knew the formula for the infinite series a/(1-r). Good enough he thinks, and sums 1+2+4+… = -1, then subtracts off the excess terms 32+64+128+… = -32, and gets the correct answer of 31.

      • crwth@piefed.zip
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        7 hours ago

        Indeed, and would have earned full marks had he said that, or even showed any awareness that his intermediate results were somehow nonstandard.

  • Nima@leminal.space
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    8 hours ago

    i thought the first one ended with “after 4 orders the bartender says ‘you guys suck’ and pours two beers.”

  • SwingingTheLamp@piefed.zip
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    9 hours ago

    This bar’s pricing makes no sense whatsoever. One beer is $1. One and 3/4 beers is also $1. Maybe they round down? Then, everybody should order 0.9999… beer, except that for some reason seventy-two beers is -$1? Weird.

    • sepiroth154@feddit.nl
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      9 hours ago

      They mean that the sequences go on forever, but the joke definitely doesn’t make that clear.

      • SwingingTheLamp@piefed.zip
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        8 hours ago

        Too subtle a joke, I guess. The description is just missing “and so on.” But the “and so on” is the crux of the bullshit in the mathematical “proof” referenced.