The equation should be
c n = 2 L x ( e n π L y / L x − e − n π L y / L x ) ∫ 0 L x f ( x ) sin n π x L x d x . {\displaystyle c_{n}={\frac {2}{L_{x}\left(e^{n\pi L_{y}/L_{x}}-e^{-n\pi L_{y}/L_{x}}\right)}}\int _{0}^{L_{x}}f(x)\sin {\frac {n\pi x}{L_{x}}}dx.}
Return to errata.
