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[–] 173 points 2 years ago* (7 children)

What about plain old x = -10?

-10 ^ 2 = 100
-10 ^ 3 = -1000
-10 ^ 5 = -100000

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  • [–] 68 points 2 years ago (1 child)

    That's what he wrote, I imagine.

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  • [–] 17 points 2 years ago (1 child)
  • [–] 101 points 2 years ago (2 children)

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

    Explanation of mathsx = -10, i = √-1 so i² = -1 and 10i²=-10

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  • [–] 15 points 2 years ago (1 child)

    Found the math but no explanation.

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  • [–] 15 points 2 years ago (1 child)

    The squareroot of 100 is ±10.

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  • [–] -2 points 2 years ago (3 children)

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

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  • [–] 4 points 2 years ago (1 child)

    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.

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  • [–] 5 points 2 years 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.

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  • [–] 37 points 2 years ago (1 child)

    Wait, isn’t x just -10 if x^3 is not 1000?

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  • [–] 27 points 2 years ago

    that is a very long way to write -10

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  • [–] 13 points 2 years ago (2 children)
  • [–] 10 points 2 years ago (2 children)

    What an extremely unnecessary explanation. As a math teacher I would have deducted points for this answer.

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  • [–] 1 point 2 years ago

    Unless I was in that clas where we had to write mathematical proofs. I HATED those. Sure, you solved the question but write out this complicated reason for why your answer is the correct answer.

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  • [–] 9 points 2 years ago (1 child)

    No definition what values are suitable for x.

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  • [–] 21 points 2 years ago (4 children)

    x has to be -10, right? Or am I missing something?

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  • [–] 6 points 2 years ago (2 children)

    Yeah, I think the point is that the person answering was wrong/over complicating. If x=10i, then x^2 would be -100 (or potentially -10 depending on what you think the ^2 is applied to).

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  • [–] 3 points 2 years ago (1 child)

    Probably what they were going for, but there are literally an infinite number of exotic arithmetic spaces you could ask this question in. For example, x=10 works in any ring with a modulus greater than 100 and less than 1000.

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  • [+] 3 points 2 years ago (1 child)