I'm having some trouble to prove the following tensor identity shown below in Einstein's summation convention:(adsbygoogle = window.adsbygoogle || []).push({});

[tex](a_{ij}+a_{ji})x_{i}x_{j}=2a_{ij}x_{i}x_{j}[/tex]

I expanded the terms but when I did group them I didn't get the identity. The only way I could get the identity is if

[tex]a_{ij}=a_{ji}[/tex]

and I don't see a reason why this would be so.

Obviously I'm missing something. Can somebody tell what is it that I'm doing wrong?

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# Tensor identity - Help

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