How to Derive the Dual Frame Vector in Terms of Connection Components?

BOAS
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Homework Statement



Use the relation ##\langle \vec e^a, \vec e_b \rangle = \delta^a_b## and the Leibniz rule to give an expression for the derivative of a dual frame vector ##\frac{\partial \vec e_b}{\partial x^a}## in terms of the connexion components.

Homework Equations

The Attempt at a Solution



I'm not sure how to do this, but this is what I've got so far:

##\partial_c \langle \vec e^a, \vec e_b \rangle = 0##

##\langle \partial_c \vec e^a, \vec e_b \rangle + \langle \vec e^a, \partial_c \vec e_b \rangle = 0##

##\langle -\Gamma^b_{dc} \vec e^d, \vec e_b \rangle + \langle \vec e^a, \Gamma^d_{bc} \vec e_d \rangle = 0##

##\Gamma^d_{bc}\langle \vec e^a, \vec e_d \rangle - \Gamma^b_{dc} \langle \vec e^d, \vec e_b \rangle = 0##
 
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BOAS said:
##\langle \partial_c \vec e^a, \vec e_b \rangle + \langle \vec e^a, \partial_c \vec e_b \rangle = 0##

##\langle -\Gamma^b_{dc} \vec e^d, \vec e_b \rangle + \langle \vec e^a, \Gamma^d_{bc} \vec e_d \rangle = 0##
Between these lines you are using what you are supposed to show ...
 
Orodruin said:
Between these lines you are using what you are supposed to show ...

##\frac{\partial \vec e_b}{\partial x^a} = \Gamma^c_{ba} \vec e_c## was presented as a definition to me, so I'm not sure how I can bring in the connection components without using that fact. (Though I do appreciate your point)
 
That is not the derivative of the dual basis vector, it is the derivative of the tangent basis vector.
 
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