Can you solve the Kronecker identity?

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spaghetti3451
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I'd like to see how many people can explain this identity:

[tex]\frac{\partialx_{i}}{\partialx_{j}} = \delta_{ij}[/tex]
 
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[tex] \frac{\partial x_{i}}{\partial x_{j}} = \delta_{ij}[/tex]
 
is what i meant.
 
It means that ∂xi / ∂xj is 1 if i=j and 0 if i≠j. In general δi,j is 1 if i=j and 0 if i≠j.
 
If i=j, then the partial derivative of xi with respect to itself is 1. If i does not equal j, then assuming that xi is not dependent on xj, then the partial derivative of xi with respect to xj is 0. The Kronecker Delta is defined such that the same holds true (when i=j, it's equal to 1, and otherwise it's 0).