Energy-momentum tensor, lagrangian density

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Homework Statement



I try to calculate the energy tensor, but i can't do it like the article, and i don't know, i have a photo but it don't look very good, sorry for my english, i have a problem with a sign in the result

Homework Equations





The Attempt at a Solution



In the photos you can see the attemp at a solution
 

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This is the problem
 

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I must get the yellow (3) from yellow in (2)
 
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