• rasensprenger@feddit.de
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    10 months ago

    The square root of x is usually defined as the positive real number that squares to x, so x^2 = 4 => x = ±2 but sqrt(4) = 2, not ±2

    The complex sqrt function is multivalued, but that opens a whole other can of worms

    • digdug@kbin.social
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      10 months ago

      And even if you allowed sqrt(4) = ±2, it would still be invalid to evaluate it to -2 on one side of the equation, but then use +2 on the other side.

      • 0x4E4FOP
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        10 months ago

        Of course, you can only choose one at a time, not mix and match, lol 😂.

    • 0x4E4FOP
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      10 months ago

      Oh yeah, you’re right, now I remembered 🤦. Been a while 😂, almost 20 years.