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    y=x/(x+3)^-1/2

    so I have differentiated using quotient rule and got:

    X/2(x+3)^-1/2 - (x+3)^1/2
    ---------------------------------
    (x+3)

    I then multiplied denominator and numerator by 2, to get rid of the fraction.

    x(x+3)^-1/2 - 2(x+3)^1/2
    --------------------------------------
    2(x+3)


    This is completely different from the answer at the back):
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    Please post a picture of the question or post it in a easy way to read...
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    (Original post by NNB_Herath)
    Please post a picture of the question or post it in a easy way to read...
    Simply how would so you differentiate this equation using quotient rule:

    y=x/(x+3)^-1/2
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    i am confused how this equation looks like ....
    is (x+3) a denominator ??
    or (x+3)^-1/2 ... a denominator...
    Post it clearly please
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    Name:  a.PNG
Views: 2
Size:  5.9 KBIs it this ??
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    (Original post by BULL14)
    Simply how would so you differentiate this equation using quotient rule:

    y=x/(x+3)^-1/2
    You mean, \displaystyle \frac x {\sqrt{x+3}}?

    Using the quotient rule, you have

    \begin{equation*}\displaystyle \frac{\frac{\mathrm d}{\mathrm dx}(x)\sqrt{x+3} - \frac{\mathrm d}{\mathrm dx}(\sqrt{x+3})x}{x+3}\end{equat  ion*}

    Looking at your working, it looked like you did it the wrong way around, ie. g'f -f'g instead f'g - fg'. As a recap, the quotient rule is,

    \begin{equation*}\displaystyle \left(\frac f g\right)' = \frac{f'g - fg'} {g^2} \end{equation*}
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    (Original post by BULL14)
    y=x/(x+3)^-1/2

    so I have differentiated using quotient rule and got:

    X/2(x+3)^-1/2 - (x+3)^1/2
    ---------------------------------
    (x+3)

    I then multiplied denominator and numerator by 2, to get rid of the fraction.

    x(x+3)^-1/2 - 2(x+3)^1/2
    --------------------------------------
    2(x+3)


    This is completely different from the answer at the back):
    As has been said above, you have some errors. Once you have sorted them out, take out a factor of (x+3)^-1/2 from the top (I chose this as the lower power of (x+3)). You will then be able to simplify the bracket that is left.
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    Post your question clearly ....
    This is confusing
 
 
 
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