In writing Eqs. 9.76 and 9.77, I tacitly assumed that the reflected and transmitted wave...

In writing Eqs. 9.76 and 9.77, I tacitly assumed that the reflected and transmitted waves have the same polarization as the incident wave—along the x direction. Prove that this must be so. [Hint: Let the polarization vectors of the transmitted and reflected waves be

and prove from the boundary conditions that θ_T = θ_R = 0.]

Reference equation 9.76

Reference equation 9.77