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I have a Vector $F = \frac {\bf r}{\|{\bf r}\|}$ where $r = xi+yj+zk$ I want to find

$$\iint F \cdot n dS$$

using the divergence theorem, where S is a sphere of radius 2 centered at the origin.

Now, I know that $F = n$ (both are unit normal vectors), and when I take that I get

$$\iint 1 dS $$, which should be the surface area of the sphere.

But how do I do this problem using divergence theorem? I tried finding the divergence, and using spherical coordinates, but I get a $ln(0)$ term. How do I do this?

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