A plane electromagnetic wave travels in an anisotropic dielectric (principal permittivities E, C.) along xy-plane making an angle of owith x-axis. Show that this wave can have at most two polarizations and hence obtain the effective RI's seen by the two polarizations of the wave. The equation of an index ellipsoid is given by 4 + 2pxy = 1in any arbitrary Cartesian coordinates, where p is a constant. Determine the RI's in principal axes system