• 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.

    • Dalvoron@lemm.ee
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      10 months ago

      I teach maths and one of the analogies is use is watching a film of someone walking forwards and backwards. If you play the film forwards (multiplying by positive), you can see the person walking forwards and backwards as normal. If you play the film backwards (multiplying by negative) you see the opposite. So multiplying by negative reverses whatever was happening before. Hard to put into words but the visuals (hopefully) seem to explain it well enough.

    • pythonoob@programming.dev
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      10 months ago

      My math teacher in middle school explained it with love/hate, but same set up.

      If you hate to love you’re a hater If you love to hate you’re a hater

    • whereBeWaldo@lemmy.dbzer0.com
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      10 months ago

      This is basically the staple way of explaining the topic in my country. It was a very bizzare concept for 13 year old me so it made understanding it a lot easier.

      • Lvxferre@lemmy.ml
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        10 months ago

        Sorry for the question, but where are you from? I learned this with my mother, so I don’t know if it’s something common here (Brazil) or something that she picked from her Polish or Italian relatives.