• PhobosAnomaly@feddit.uk
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    1 day ago

    Alright, education time needed!

    I’m a fair few years out from my entry level uni maths module, so:

    In between the second and third step of the solution, why is 1a / 2√a = 6

    not evaluating as

    a/√a = 12 ?

    • sacredfire@programming.dev
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      1 day ago

      It does, he just didn’t show that a/√a simplifies to √a. There are a couple ways to think about it, but the simplest is if you just wanna get rid of the square root in the denominator, you can multiply the entire left side by (√a/√a) which gives you a√a / √a√a. This then turns into a√a/a. From there you get to just √a

      • PhobosAnomaly@feddit.uk
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        1 day ago

        Fucking hell, thank you. I thought I was going quite mad - I’d just taken a detour in solving it instead.

        Cheers friend!

    • eta@feddit.org
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      1 day ago

      a = (√a)^2 = √a √a

      Then you have (√a √a) /(2 √a) = 6 and can cross out one √a and multiply by 2 to get √a = 12