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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: 18
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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    (Original post by NNB_Herath)
    Post your question clearly ....
    This is confusing

    1. I'm also taking IAL and wondering if you could help me out.I'm taking the same subjects as you and have just started AS level.Can you tell me what book you used for biology,chemistry and physics.How many hours did you study from october vs nearer to the exams.Whattechnique to you recommend I use if I want to achieve 4as in my AS year(I'm doing maths too).Also,should I use the green student book by ann fulick for biology?Which book is better for physics: Hodder or the red student book by miles hudson? 0
 
 
 
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