Problem 4.158

Find the radius vector defining the position of a point source of spherical waves if that source is known to be located on the straight line between the points with radius vectors $\mathbf{r}_ {1}$ and $\mathbf{r}_ {2}$ at which the oscillation amplitudes of particles of the medium are equal to $a_{1}$ and $a_{2}$. The damping of the wave is negligible, the medium is homogeneous.