We have seen that kx and ky decides the direction of propagation of a plane wave. Show that the magnitude u(x, y, z) of an arbitrary electric field (to be specific, this electric field is a component of the electromagnetic wave) can be written as a superposition of infinite number of plane waves traveling along different directions. [Hint: think about time and frequency dependence of signals. You may also need to review the basics of double integrals]

We have seen that kx and ky decides the direction of propagation of a plane wave. Show that the magnitude u(x, y, z) of an arbitrary electric field (to be specific, this electric field is a component of the electromagnetic wave) can be written as a superposition of infinite number of plane waves traveling along different directions. [Hint: think about time and frequency dependence of signals. You may also need to review the basics of double integrals]