Find an expression for a magnetic field from a given electric field

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TechieDork
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Homework Statement
Find an expression for a magnetic field B(X,t) from a given electric field in a monochromatic plane wave solution E(X,t) using Maxwell's equations.
Relevant Equations
E(X,t) = εe^i(kX-ωt) , X = (x1,x2,x3) , k = (kx1,kx2,kx3) , ω = c|k| , k·ε = 0
ε is a complex vector
Here this is my attempt :

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Reference Textbook : Zangwill's Modern Electrodynamics

I stuck at the last step , I really have no idea what to do next.
 
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You have not split [itex]\mathbf{E}[/itex] into its components correctly. The [itex]\mathbf{x}_1[/itex] component of [itex]\mathbf{E}[/itex] should be [itex]\epsilon_1 e^{i(\mathbf{k}\cdot \mathbf{x} - \omega t)} = \epsilon_1 e^{i(k_1x_1 + k_2x_2+k_3x_3 - \omega t)}[/itex], etc.

But you don't need to split this into components.

The electric field depends on [itex]\mathbf{x}[/itex] only through a constant vector times a scalar function of the dot product, so its curl is computed most easily by the chain rule: [tex] \nabla \times (\mathbf{c}f(\zeta(\mathbf{x}))) = f'(\zeta) ((\nabla \zeta) \times \mathbf{c}).[/tex]
 
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