Consider a sinusoidal electromagnetic wave with fields E$=$Emaxj$^$sin$($kx$$t$)$E$=$Emaxj$^$sin$($kx$$t$)$ and B$=$Bmaxk$^$sin$($kx$$t$+)$B$=$Bmaxk$^$sin$($kx$$t$+),$ with $$$$$$$$$.$ E$$E$$ and B$$B$$ are to satisfy equations Ey$($x$,$t$)$x$=$Bz$($x$,$t$)$tEy$($x$,$t$)$x$=$Bz$($x$,$t$)$t and $$Bz$($x$,$t$)$x$=0$$0$Ey$($x$,$t$)$t$$Bz$($x$,$t$)$x$=0$$0$Ey$($x$,$t$)$t$.$