\[ \boxed{ {\frac {\rm d}{{\rm d}x}}y \left( x \right) -\sqrt { \left( {\it b4}\, \left( y \left( x \right) \right) ^{4}+{\it b3}\, \left( y \left( x \right) \right) ^{3}+{\it b2}\, \left( y \left( x \right) \right) ^{2}+{\it b1}\,y \left( x \right) +{\it b0} \right) \left( {\it a4}\,{x}^{4}+{\it a3}\,{x}^{3}+{\it a2}\,{x}^{2}+{\it a1}\,x+{\it a0} \right) }=0} \]