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Chain rule help

  1. Aug 12, 2012 #1
    Can someone help me out with what I believe who.d be a straight chain rule application?

    D/dx (dy/dx)^2

    I would think, applying the chain rule, you get

    2 (dy/dx) d/dx (dy/dx) = 2 (dy/dx) (d2y/dx2)

    But, from the papers I checked, the (dy/dx) in the answer goes away, leaving just

    2 (d2y/dx2)

    What am I missing?
  2. jcsd
  3. Aug 12, 2012 #2
    Can you rewrite your question in LaTex? I don't quite follow what you are saying.
  4. Aug 12, 2012 #3


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    Dearly Missed

    If you have referred correctly to the paper, the paper is wrong.
  5. Aug 12, 2012 #4
    Sorry everyone, ignore this.
  6. Aug 12, 2012 #5
    Thanks arildo, especially for the light speed reply. The paper was right, it was I who was wrong. I did not realize the paper was differentiating by y not x. Mea culpa.
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