Exercise 3.2.15

Use Exercise an exercise given elsewhere in the book to find an equation of a plane containing the two vectors $\mathbf{p}$ and $\mathbf{q}$ and the point $0$. Hint: If $(x,y,z)$ is a point in this plane, the volume of the parallelepiped determined by $(x,y,z)$ and the vectors $\mathbf{p}$, $\mathbf{q}$ equals 0.