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Math Help - Math functions of functions.

  1. #1
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    Math functions of functions.

    Suppose that f(5) = -1, f'(5) = 2, g(5) = 5, g'(5)=-3
    find (g/(f^2+g))' (5).

    I must be doing something wrong. Because my answer is way off. Or maybe it's because I'm not understanding the notation properly.
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  2. #2
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    Quote Originally Posted by pewpew01 View Post
    Suppose that f(5) = -1, f'(5) = 2, g(5) = 5, g'(5)=-3
    find (g/(f^2+g))' (5).

    I must be doing something wrong. Because my answer is way off. Or maybe it's because I'm not understanding the notation properly.
    quotient rule and chain rule, correct?

    \displaystyle \left(\frac{g}{f^2+g}\right)' = \frac{(f^2+g) \cdot g' - g(2f \cdot f' + g')}{(f^2+g)^2}

    now sub in your given values and determine the derivative at 5
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  3. #3
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    Oh... right. Chain rule and quotient. How could I forget about it.
    kk thanks.
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