I am having a problem that is glossed over in many text books but is driving me nuts.(adsbygoogle = window.adsbygoogle || []).push({});

Consider the following inner product or one-form with a vector argument:

dx_i(partial_j) = kroenicker delta ij

Here, dx_i is a one-form and partial_j (the partial wrt x_j) is a vector.

Some books say:

dx_i(partial_j) = partial x_i / partial x_j = kroenicker delta ij

The problem is that I can't see how this is true. (Well, I do know that partial x_i / partial x_j = kroenicker delta ij but I can't see the rest.) What am I missing here?

Thanks.

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# Differential Geometry/Ricci Calculus Question

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