• paholg@lemm.ee
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      1 year 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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        1 year 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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          1 year 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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            1 year 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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              1 year 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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            1 year 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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              1 year 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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            1 year 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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          1 year ago

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