Solving Lorentz Condition with Lagrangian

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Homework Statement


Given the Lagrangian
<br /> L = -\frac{1}{2}\partial_{\alpha}A_{\beta}\partial^{\alpha}A^{\beta} + \frac{1}{2}\partial_{\alpha}A^{\alpha}\partial_{\beta}A^{\beta} + \frac{\mu^2}{2}A_{\beta}A^{\beta}

show that A satisfies the Lorentz condition \partial_{\alpha}A^{\alpha} = 0.


Homework Equations





The Attempt at a Solution


I want to say we can treat \partial_{\alpha}A^{\alpha} as an independent field, and find the appropriate field equations for it, but I'm not sure if that makes sense. Any thoughts?
 
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Upon further thought, this seems like a good time to use Noether's theorem...
 
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