\[
\boxed{
{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left( x \right) ={\frac {2\,{\it JacobiSN} \left( x,k \right) {\it JacobiCN} \left( x,k \right) {\it JacobiDN} \left( x,k \right) {\frac {\rm d}{{\rm d}x}}y \left( x \right) -2\, \left( 1-2\, \left( {k}^{2}+1 \right)  \left( {\it JacobiSN} \left( a,k \right)  \right) ^{2}+3\,{k}^{2} \left( {\it JacobiSN} \left( a,k \right)  \right) ^{4} \right) y \left( x \right) }{ \left( {\it JacobiSN} \left( x,k \right)  \right) ^{2}-{\it JacobiSN} \left( a,k \right) }}=0}
\]