\[
\boxed{
{\frac {\rm d}{{\rm d}x}}y \left( x \right) ={\frac {{b}^{3}+ \left( y \left( x \right)  \right) ^{2}{b}^{3}+2\,y \left( x \right) {b}^{2}ax+{x}^{2}b{a}^{2}+ \left( y \left( x \right)  \right) ^{3}{b}^{3}+3\, \left( y \left( x \right)  \right) ^{2}{b}^{2}ax+3\,y \left( x \right) b{a}^{2}{x}^{2}+{a}^{3}{x}^{3}}{{b}^{3}}}=0}
\]