• paholg@lemm.ee
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    8 months ago

    Pssh, I’ll divide by zero all day. You just need -infinity=infinity (think a number circle instead of a number line), and you’re good.

    It’s 0/0 where the real crimes begin.

    • blind3rdeye@lemm.ee
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      8 months ago

      Yep. ∞ is infinitely big in the same way that 0 is infinitely small. -0 = 0 and -∞ = ∞. Opposite ends of the circle. (Or the Riemann sphere if you like complex numbers.)

      • raspberriesareyummy@lemmy.world
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        8 months ago

        While this Riemann sphere seems like a useful concept, -∞ = ∞ is an observation that doesn’t seem to hold true outside this spherical model of complex numbers. Just add ∞ to the both sides, and you end up with 0 = ∞ + ∞ which is most certainly not true.

        • Kühe sind toll@feddit.de
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          8 months ago

          0 = ∞ + ∞ which is most certainly not true.

          This is only true if both infinite are the same, but one is negative. As a general statement you’re right, that this is not true.

          • raspberriesareyummy@lemmy.world
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            8 months ago

            Well - in the post I replied to there was explicit talk about +∞ and -∞, upon which I believe it is fair to say that ∞ is positive in this example.

        • MBM@lemmings.world
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          8 months ago

          Just add ∞ to the both sides

          That’s why ∞ - ∞ is left undefined (same as 0/0 and ∞/∞)

          • raspberriesareyummy@lemmy.world
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            8 months ago

            adding ∞ to both sides does not create a ∞ - ∞ situation, though. The substraction is a whole different topic, because it becomes an elimination problem, whereas ∞ + ∞ = ∞

        • blind3rdeye@lemm.ee
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          8 months ago

          Sure. And it also doesn’t help to avoid the problems with division by zero. But lucky we’re posting in the shitpost section, so we don’t have to worry too much about details.

      • SchizoDenji@lemm.ee
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        8 months ago

        For an easy approximation by this rule, just differentiate both numerator and denominator by the same variable and apply the limits again.