Consider the electric dipole of Example 21.14. (a) Derive an expression for the magnitud...

Consider the electric dipole of Example 21.14. (a) Derive an expression for the magnitude of the electric field produced by the dipole at a point on the x -axis in Fig. 21.33. What is the direction of this electric field? (b) How does the electric field at points on the x -axis depend on x when x is very large?