• Deebster
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    4 months ago

    When all you have is an imaginary hammer, everything looks like a rotation around the imaginary unit circle.

    Explanation of maths

    x = -10, i = √-1 so i² = -1 and 10i²=-10

      • JackbyDev
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        4 months ago

        The squareroot of 100 is ±10.

        • OozingPositron@feddit.cl
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          4 months ago

          The square root is always positive, but you can plug it into the quadratic formula to get the two possible values.

          • JackbyDev
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            4 months ago

            Okay, fine the square roots of 100 are ±10.

            • sevenapples@lemmygrad.ml
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              4 months ago

              That’s not how the square root is defined.

              You’re confusing “square root of 100” with “the answer to x^2 = 100”. These are different things.

              • JackbyDev
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                4 months ago

                Which is why I differentiated between square roots and the principle square root by saying the square roots instead of the square root on the second comment.

          • ShrimpCurler@lemmy.dbzer0.com
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            4 months ago

            There’s no reason to bring the quadratic formula into this. Square roots can be negative, but when talking about the square root it’s normally assumed to be the principal square root, which is the positive one.

          • mexicancartel@lemmy.dbzer0.com
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            3 months ago

            Nope. To clarify, square roots are the opposite of squaring.

            Now ask yourself:

            What is 10² ?

            What is (-10)² ?

            If you get the same answer, then they are both the roots of the answer. +10 and -10 then gets together called ±10

    • fx3@beehaw.org
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      4 months ago

      IIRC, your spoilery “so” is the other way round. The right side is the definition, and the left-hand side a layman’s shorthand, as the root operator isn’t defined on negative numbers.

      I might very well be wrong. My being a mathematician has been over for a while now, my being a pedantic PITA not though.

      • Deebster
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        4 months ago

        I don’t know enough to know how correct your pedantry is (technically or not), but to explain the meme it made sense to go through the symbols in the order you see them. I never got any points from the proof questions in exams anyway.