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    Hello,

    I have not yet studied differential equations and have come across a proof that, I think, involves them.

    If possible, could someone please explain to me how, if x=az, dx=adz.

    Additionally, how, if x=(z^n), dx=n(z^(n-1))

    Thank you
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    The notation dx = a\, dz is sloppy notation which is only used when you intend to do something else with it. What it means is that \dfrac{dx}{dz} = a, which is fairly obvious given that x=az!

    Similarly, if x = z^n then \dfrac{dx}{dz} = nz^{n-1}. We can write dx = nz^{n-1}dz when it's convenient, but only for the sake of notation.
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    http://www.thestudentroom.co.uk/show...2#post27083342
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    (Original post by nuodai)
    The notation dx = a\, dz is sloppy notation which is only used when you intend to do something else with it. What it means is that \dfrac{dx}{dz} = a, which is fairly obvious given that x=az!

    Similarly, if x = z^n then \dfrac{dx}{dz} = nz^{n-1}. We can write dx = nz^{n-1}dz when it's convenient, but only for the sake of notation.
    Thank you very much. You have helped me lots today and both on questions I really should have been able to do myself. I am rusty
 
 
 
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Updated: September 30, 2010
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