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    (Original post by Dinaa)
    I don't know, I'm confused
    The only reason I would be dividing is if I had multiplied by something in the first place...

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    Another question :awesome:

    y= x^2 + 3x^1/2

    a) Find dy/dx

    dy/dx= 2x + 3/2x^-1/2

    b) Show that 2x d^2y/dx^2 + dy/dx - 6x = 0

    d^2y/dx^2= 2 -3/4x^-3/2

    I was confused here but still carried on to do:

    2x(2 - 3/4x^-3/2) + (2x+3/2x^-1/2) - 6x

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

    but now.. what?
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    (Original post by samb1234)
    The only reason I would be dividing is if I had multiplied by something in the first place...

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    So..
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    Very Important Poster
    (Original post by Dinaa)
    So..
    So, you take out the x^3/2 and put it on the bottom. And then complete the square.
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    (Original post by Dinaa)
    So..
    Multiply your differential by what you end up dividing by

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