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Second Order Differential (further maths)

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    Hi Guys, I need help on question 3. May i know how to reduce the differential equation?Name:  14502938_1314201781924710_1777947431093970643_n.jpg
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    differentiate z = y3 with respect to x

    the first derivative will enable you to find an expression for dy/dx

    the second derivate will enable you to find an expression for d2y/dx2

    work with these to get the result they ask for.
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    (Original post by marcuskhoo)
    Hi Guys, I need help on question 3. May i know how to reduce the differential equation?Name:  14502938_1314201781924710_1777947431093970643_n.jpg
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    Differentiate  z=y^3 twice with respect to x. Use these results to substitute everything in the first equation involving y into something in terms of z and x.
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    (Original post by marcuskhoo)
    Hi Guys, I need help on question 3. May i know how to reduce the differential equation?
    z=y^3

    \frac{dz}{dx}=3y^2\frac{dy}{dx}

    \frac{d^2z}{dx^2}=3y^2\frac{d^2y  }{dx^2}+6y(\frac{dy}{dx})^2

    and proceed with substitutions
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    (Original post by RDKGames)
    z=y^3

    \frac{dz}{dx}=3y^2\frac{dy}{dx}

    \frac{d^2z}{dx^2}=3y^2\frac{d^2y  }{dx^2}+6y(\frac{dy}{dx})^2

    and proceed with substitutions

    Hey bro, its you again. Thanks man, instead of doing second derivative in terms of dz/dx, I did dy/dx which is a longer method and i did mistakes there too... thanks for your help!

    Cheers and good day ahead.
 
 
 
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