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    Hi All, working through an FP3 AQA Past paper - im on a reasonably horrible 2nd order differential equation:

    I can't fully understand how they get from line 2 working (which I have) to line 3. I realise that they've simplified the (dx/dt)*(dy/dx) in line two to give dy/dt in line three. But how they get from x*(d/dt)*(dy/dx) in line 2 to x*(dx/dt)*(d/dx)*(dy/dx) in line three is a mystery! Any help or pointers would be greatly appreciated

    Thanks again

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    Dont worry people - misread something :cool:
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    (Original post by Hunarench95)
    Hi All, working through an FP3 AQA Past paper - im on a reasonably horrible 2nd order differential equation:

    I can't fully understand how they get from line 2 working (which I have) to line 3. I realise that they've simplified the (dx/dt)*(dy/dx) in line two to give dy/dt in line three. But how they get from x*(d/dt)*(dy/dx) in line 2 to x*(dx/dt)*(d/dx)*(dy/dx) in line three is a mystery! Any help or pointers would be greatly appreciated

    Thanks again

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    \displaystyle \frac{d}{dt}=\frac{d}{dx}\cdot \frac{dx}{dt}
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    (Original post by ztibor)
    \displaystyle \frac{d}{dt}=\frac{d}{dx}\cdot \frac{dx}{dt}
    Thanks bud - a lot more straight forward than I thought it would of been (I was looking for something a lot more complex!!)
 
 
 
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