\[ \boxed{ {\frac {\rm d}{{\rm d}x}}y \left( x \right) ={\frac {{\it \_F1} \left( \left( y \left( x \right) \right) ^{2}-2\,\ln \left( x \right) \right) }{\sqrt { \left( y \left( x \right) \right) ^{2}}x}}=0} \]