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Is this valid?

  1. Sep 11, 2010 #1
    I am wondering if this is valid.

    (de/dx) + (1/p)(dP/dx) = (1/dx)(de +(1/p)dP)

    Basically are you allowed to pull a 1/dx out of the equation?
     
  2. jcsd
  3. Sep 11, 2010 #2
    What would 1/dx even mean?
     
  4. Sep 12, 2010 #3

    Pengwuino

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    Yes it is possible, although a mathematician would not like it :biggrin:. There are certain requirements the function must meet before you are allowed to treat the differentials like parts of a fraction which I don't know off the top of my head.
     
  5. Sep 12, 2010 #4
    Thanks for the replies. I am not sure what 1/dx would mean. In fact that is why I am asking this question, because I didn't think it would mean anything and therefore is wrong.
     
  6. Sep 12, 2010 #5

    Pengwuino

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    Let's say I have [tex] {df \over dt} = 3t^2[/tex] and you just pulled out the 1/dt to get [tex]{1 \over {dt}}(df) = 3t^2[/tex]. There is nothing special going on.
     
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