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Math Help - Help needed deriving

  1. #1
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    Help needed deriving

    Hi there- would appreciate some pointer on deriving this function, if someone would be so kind. Thank you!


    g(x) = [16+x-8squareroot(x)]/[(squareroot(x)-4)]
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  2. #2
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    You want to use the quotient rule: f'\left(\frac{u(x)}{v(x)}\right)=\frac{v(x)u'(x)-v'(x)u(x)}{v(x)^2}

    Here u'(x)=1-8x^{-\frac{1}{2}} and v'(x)=x^{-\frac{1}{2}}
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  3. #3
    MHF Contributor Drexel28's Avatar
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    ...deriving this equation...
    Just a note, the term you are looking for is differentiating. Deriving would mean that you took some other equation and manipulated it into the current one.
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  4. #4
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    Got it, thank you. I don't need the final answer, but with that method, I get a long string of terms. If that's normal, I'll keep going, though whenever that happens, I also feel like I screwed up.
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  5. #5
    MHF Contributor Drexel28's Avatar
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    Quote Originally Posted by rhunt View Post
    Got it, thank you. I don't need the final answer, but with that method, I get a long string of terms. If that's normal, I'll keep going, though whenever that happens, I also feel like I screwed up.
    That is kind of vague. Derivatives of rational functions can tend to get really messy, though they usually simplify. Try wolframalpha.com to see if your answer is correct.
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