Solution
= Solution
Continuity of normal velocity and pressure at each density interface requires continuity of $\widehat w$ and $d\widehat w/dz$ at $z=±L$. These four conditions determine the four unknown amplitudes.
= Solution
Continuity of normal velocity and pressure at each density interface requires continuity of $\widehat w$ and $d\widehat w/dz$ at $z=±L$. These four conditions determine the four unknown amplitudes.