• Lvxferre@lemmy.ml
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    10 months ago

    That’s surprisingly accurate, as people here are highlighting (it makes geometrical sense when dealing with complex numbers).

    My nephew once asked me this question. The way that I explained it was like this:

    • the friend of my friend is my friend; (+1)*(+1) = (+1)
    • the enemy of my friend is my enemy; (+1)*(-1) = (-1)
    • the friend of my enemy is my enemy; (-1)*(+1) = (-1)
    • the enemy of my enemy is my friend; (-1)*(-1) = (+1)

    It’s a different analogy but it makes intuitive sense, even for kids. And it works nice as mnemonic too.

  • saltesc@lemmy.world
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    10 months ago

    It’s not that hard.

    If you have -3 -3s and I give you one, you now only have -2 -3s. If you want to get to a total of -6, I have to hand over 4 more -3s to get there, the first 3 of them just being what’s needed to get you to 0 and out of deficit. Now you get to hold onto the next two I hand over, and now you have 2 -3s which total -6. But that’s 15 worth of -3s I had to hand over to get you there and -6 + 15 = 9, like -3 × -3 does too.

    Negative numbers aren “real”. Like 0, they’re just a concept used to represent something, deficit.

    • Hupf@feddit.de
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      10 months ago

      Negative numbers aren “real”.

      You’re imagining things. Naturally such a complex construct seems irrational at times, but some day you will get the whole thing

      • MotoAsh@lemmy.world
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        10 months ago

        Fun fact: exponents and multiplication DO work like rotation … in the complex domain (numbers with their imaginary component). It’s not a pure rotation unless it’s scalar, but it’s neat.

        I know I explained that the worst ever, but 3blue1brown on YT talks about it and many other advanced math concepts in a lovely intuitive way.