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**1. Homework Statement**

This question refers to Griffiths E and M book.

Of course I am stuck with the integral.

I chose z to be in the same direction as the polarization.

The integral is then

[tex]P \int d\Omega r'^2 dr'\frac{\left(\mathbf{r} -\mathbf{r'}\right)\cdot \hat{\mathbf{z}}}{\left(\mathbf{r} -\mathbf{r'}\right)^2}[/tex]

BTW, how do you get the script r that Griffiths uses in latex?

**2. Homework Equations**

**3. The Attempt at a Solution**