Covarient Maxwell: Explaining 2nd Line From Attachment

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can some tell me why the second line follows from the first in the attachment

thank you
 

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  • Schermafbeelding 2015-02-23 om 16.29.21.png
    Schermafbeelding 2015-02-23 om 16.29.21.png
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It doesn't. The two sides of the equation have different free indices.
 
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Orodruin said:
It doesn't. The two sides of the equation have different free indices.
thanx!
 
For some reason they have mad a swap ##\mu\leftrightarrow\nu## in the second line...and also switch the order of the partial derivatives.
 

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