Chapter 1.2, Problem 1.13P

(a)

To determine

To show that $\nabla \cdot \left(r^2\right)=2\overrightarrow{r}$ .

(b)

To determine

To show that $\nabla \cdot \left(\frac{1}{r}\right)=-\frac{\widehat{r}}{r^2}$ .

(c)

To determine

The general expression for $\nabla \cdot r^n$ .