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criitz@reddthat.com ⁨7⁩ ⁨months⁩ ago

You’re correct. The square root operator only returns the principal root (basically, the positive one).

So if x ^2^ = 9 then x = ±√9 = ±3

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UnRelatedBurner@sh.itjust.works ⁨7⁩ ⁨months⁩ ago
Thanks, I haven’t connected the dots to that (±) sign and this problem.

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Routhinator@startrek.website ⁨7⁩ ⁨months⁩ ago
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So I checked this on my smartphone first, and thought maybe the software is just shit… So then I checked it on a Casio scientific calc, and both agree.

-3^2 = -9… And 9 != -9

… Are all the calculators somehow wrong? What’s the math rule I’m forgetting here…

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- criitz@reddthat.com ⁨7⁩ ⁨months⁩ ago
  I think your calculator is interpreting that as -(3^2) and not (-3)^2
  
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  - Routhinator@startrek.website ⁨7⁩ ⁨months⁩ ago
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    Oh derp. Yep it is.
    
    Was better when calcs had a +/- button.
    
    And I remembered the math rule too.
    
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    Routhinator@startrek.website ⁨7⁩ ⁨months⁩ ago
    GD I am just realizing how long its been since I did math in my head without a programming language…
    
    I should take a math class again or something and refresh that knowledge.
    
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