Field in homogeneous domains of a medium

In domains where the values of e, p and a are constant, equations (8.1) - (8.4) take the form 

In many problems, it is useful to separate Maxwell s equations (8.8) - (8.11), i.e., to write the equations for the electric and magnetic fields separately. To do this, we will apply the curl operator Vx to the left- and right-hand sides of (8.9) and substitute the result into (8.8)  

Similarly, using the curl operator V x on (8.8) and allowing for (8.9) we arrive 

It is common knowledge (Stratton, 1941 Kong, 2000) that in the absence of extraneous electric currents and charges, free electric charges disappear (relax) very rapidly in a homogeneous medium hence, we can write 

Mciuatioiis (8.10) and (8.18), salisfioti by the vectors of the electric and inagnctic fields ill a homogeneous domain of a medium, in the absence of extraneous currents and charges, arc called homogeneous telegraph expiations. 

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