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A basic question about variation

  1. Mar 21, 2015 #1
    134936ysz2jzskiposokj9.png
    I got the result that is consist with references in fisrt case. Is there anything wrong in 2nd way?
     
  2. jcsd
  3. Mar 21, 2015 #2

    Orodruin

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    Both are wrong. In the first case you are missing a 2 in both terms (still giving the same equation if you put the variation to zero). In the second case you missed a 2 only on the first term.
     
  4. Mar 21, 2015 #3
    Thank you. I see.
    Kij=gimgjnKmn
    I should consider another Kij here.
     
  5. Mar 21, 2015 #4

    Orodruin

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    Yes, you cannot vary Kij independently of Kij.
     
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