How Can You Find Vector Potentials for a Magnetic Field?

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Homework Statement


A magnetic field of a long straight wire carrying a current I along the z-axis is given by the following expression:

[tex]\mathbf{B} = \frac{\mu_0I}{2\pi} \{\frac{-y}{x^2+y^2} \hat{x} + \frac{y}{x^2 + y^2} \hat{y} \}[/tex]

Find two different potentials that will yield this field. Show explicitly that the curl of the difference between these two potentials vanishes.

Homework Equations


[tex]\nabla \times \mathbf{A} = \mathbf{B}[/tex]

The Attempt at a Solution


I took a cross product to get this system...

[tex] \frac{\partial A_y}{\partial x} - \frac{\partial A_x}{\partial y} = 0 \\[/tex]

[tex] \frac{\partial A_z}{\partial y} - \frac{\partial A_y}{\partial z} = \frac{-y}{x^2+y^2} \\[/tex]

[tex] \frac{\partial A_x}{\partial z} - \frac{\partial A_z}{\partial x} = \frac{y}{x^2+y^2} \\[/tex]

I don't know what to do! Any ideas?
 
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Maybe nobody knows how to do this problem...

But does anybody know how to, in general, find a vector 'A' given its cross product 'B'?