Deriving Maxwell divergence equations from curl equations in waveguides

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crick
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Consider a waveguide with axis parallel to axis ##z##. Using cartesian coordinates the fields inside the waveguide can be written as
Immaginiie.png

Where ##\alpha## is the wavenumber and ##k=\frac{\omega}{c}## .

The maxwell equations ##\nabla \times E=-\frac{\partial B}{\partial t}## and ##\nabla \times B=\epsilon \mu \frac{\partial E}{\partial t}## are written in components as

Immaginke.png
##\tag{(A)}##While the maxwell equations ##\nabla \cdot E=-\frac{\partial B}{\partial t}## and ##\nabla \cdot B=\epsilon \mu \frac{\partial E}{\partial t}## are written in components as

Immagikne.png

##\tag{(B)}##

On textboox it is claimed that equations ##B## are not useful, since they can obtained from equations ##A##. So how to obtain equations ##B## using equations ##A##?
 
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crick said:
∇×E=−∂B/∂t

crick said:
∇⋅E=−∂B/∂t
Are these both true? One should be a vector and one a scalar.
 
Of course, they are not true since
$$\vec{\nabla} \cdot \vec{E}=0, \quad \vec{\nabla} \cdot \vec{B}=0.$$
A vector can never ever be equal to a scalar!
 
mjc123 said:
Are these both true? One should be a vector and one a scalar.
vanhees71 said:
Of course, they are not true since
$$\vec{\nabla} \cdot \vec{E}=0, \quad \vec{\nabla} \cdot \vec{B}=0.$$
A vector can never ever be equal to a scalar!

EDIT OF THE QUESTION: I apologize, I made a mistake, I intended to write the first two maxwell equations, that are ##\nabla \cdot E=0## and ##\nabla \cdot B=0## (if there are no sources). ##E## and ##B## are intended to be vectors.
 
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