What is the transformation rule for vector-covector derivatives?

AI Thread Summary
The discussion focuses on proving the transformation rule for vector and covector derivatives under a smooth change of coordinates. The main challenge is to show that the expression X^b (d(Aa)/d(x^b) - d(Ab)/d(x^a)) transforms correctly. Initial attempts resulted in four terms, with two terms not simplifying as expected. The confusion arose from differentiating with respect to the incorrect coordinate system. Ultimately, using the chain rule and the correct coordinate system resolved the issue, leading to the desired transformation rule.
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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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