- #1

boddhisattva

- 10

- 0

## Homework Statement

Given an electric field:

E=Ex*ex+Ey*ey

with

Ex=cos(kx-wt)

Ey=cos(kx-wt+e)

where e is the phase difference

Show that

Ex^2 + Ey^2 - 2*Ex*Ey*cos(e) = ( sin(e) )^2

## Homework Equations

Ex=cos(kx-wt)

Ey=cos(kx-wt+e)

## The Attempt at a Solution

Was unable to find a solution with trigonometric relations