• UnRelatedBurner@sh.itjust.works
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      6 months ago

      Uhm, actually 🤓☝️!

      Afaik sqrt only returns positive numbers, but if you’re searching for X you should do more logic, as both -3 and 3 squared is 9, but sqrt(9) is just 3.

      If I’m wrong please correct me, caz I don’t really know how to properly write this down in a proof, so I might be wrong here. :p
      (ps: I fact checked with wolfram, but I still donno how to split the equation formally)

      • h3ndrik@feddit.de
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        6 months ago

        x^2 = 9

        <=>

        |x| = sqrt(9)

        would be correct. That way you get both 3 and -3 for x.

        That’s the way your math teacher would do it. So the correct version of the statement in the picture is: “if x^2 = 9 then abs(x) = 3”