I'm going crazy (Electromagnetic Energy-Momentum Tensor)

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Homework Statement



The problem is conveniently located here:

http://www.dur.ac.uk/resources/cpt/graduate/lectures/mscps.pdf

Problem no. 31. There's even a solution, here:

http://www.dur.ac.uk/resources/cpt/graduate/lectures/grsolns.pdf

However, I don't understand the solution. How does the antisymmetry of [tex]F^{\rho\lambda}[/tex] allow us to rewrite [tex]\nabla_\rho F_{\sigma\lambda} - \frac{1}{2} \nabla_\sigma F_{\rho\lambda}[/tex] as [tex]\frac{1}{2}\left ( \nabla_\rho F_{\sigma\lambda} - \nabla_\lambda F_{\sigma\rho} - \nabla_\sigma F_{\rho\lambda} \right )[/tex] ? I just don't see it. This implies that [tex]\nabla_\rho F_{\sigma\lambda} = -\nabla_\lambda F_{\sigma\rho}[/tex], which doesn't seem right...

Homework Equations



See above.


The Attempt at a Solution



See above.

Any help will be much appreciated!
 
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The point is that you have

[tex]F^{\rho\lambda} \nabla_\rho F_{\sigma\lambda} = \frac{1}{2} (F^{\rho\lambda}-F^{\lambda\rho}) \nabla_\rho F_{\sigma\lambda}.[/tex]

After a relabeling of dummy indices, you find the claimed result.
 
Thanks! Now it finally makes sense... :)