(adsbygoogle = window.adsbygoogle || []).push({}); Are the following identities correct?(They are under integration btw... and we are using the summation convention...)

1.) [tex]\delta_{ij}\delta_{ji}=1[/tex]

2.) [tex]\delta_{ij}a_j a_i = a^2[/tex]

3.) [tex]q_i q_j \delta_{ji} = q^2[/tex]

4.) [tex]q_i q_j a_j a_i = q^2 a^2[/tex]

My input:

kronecker delta's are equal to one if i=j and zero other wise... ?

a_i a_i = a^2... ?

q_i q_j = q^2 delta_ij... ?

Cheers

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# Homework Help: Some vector multiplications

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