What is the transformation rule for vector-covector derivatives?

deadringer
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Homework Statement


We have a vector X^a (n.b ^ indicates superscript) and covector Aa. We need to show that
X^b (d(Aa)/d(x^b) - d(Ab)/d(x^a))

transforms correctly under an artbitrary smooth change of coords. N.b the derivatives are partial.

By using the transformation rules for the vector and covector respectively I get four terms, two of which give us the required transformation rule. I can't get the other two to disappear. I'd appreciate any hints.
 
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When I do it I find the other two terms vanish because they contain a term like \frac{ \partial^2 f}{\partial x \partial y}-\frac{\partial^2 f}{\partial y \partial x}.
 
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I managed to get this. I was differentiating with respect to the wrong coordinate system, which messed up the calculation. I then tried using the chain rule and differentiating with respect to the other coord system and it all fell out.
 
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