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teachings
(mander.xyz)
A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
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This is a science community. We use the Dawkins definition of meme.
You're correct. The square root operator only returns the principal root (the positive one).
So if x^2 = 9 then x = ±√9 = ±3
That's why in something like the quadratic formula we all had to memorize in school its got a "plus or minus" in it: -b ± √...(etc)
Thanks, I haven't connected the dots to that (+-) sign and this problem.
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...
I think your calculator is interpreting that as -(3^2) and not (-3)^2
Oh derp. Yep it is.
Was better when calcs had a +/- button.
And I remembered the math rule too.
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.