Product of Levi-Civita symbols with contracted indices

Deriving a useful identity for the once-contracted product of two Levi-Civita symbols (εijk εklm) in terms of Kronecker deltas. The more general identity is here:    • Product of Levi-Civita symbols: a useful i...   About me: I studied Physics at the University of Cambridge, then stayed on to get a PhD in Astronomy. During my PhD, I also spent four years teaching Physics undergraduates at the university. Now, I'm working as a private tutor, teaching Physics & Maths up to A Level standard. My website: https://benyelverton.com/ #education #mathematics #maths #math #levicivita #tensor #contraction #summation #alternatingsymbol #epsilon #kronecker #delta #identity #product #determinant #matrix #symmetry #antisymmetric #vector #proof