Hello,

Question Details:
My professor gave the class a take-home problem that reads as follows:

A uniformly charged line segment with linear charge density λ extends from +a/2 to -a/2 on the z-axis.  Find the exact potential V(r,θ) everywhere.  (The vector r makes an angle θ to the z-axis)

The textbook we are using is Introduciton to Electrodynamics, David J. Griffiths 3rd edition.

What I have tried doing in using equation (2.30) V= \frac{1}{4*Pi*epsilon not}\int{λ/r}da, (the integral containing λ(r')). 

I'm having trouble finding the (lowercase cursive) r in the denominator, that is the distance from the charge to the vector r (see Figure 2.32).  Also I'm having trouble with the limits of integration and the finding dl.

Any help would be greatly appreciated. 

Thank You