\[ \boxed{ {\frac {\rm d}{{\rm d}x}}y \left( x \right) = \left( {\frac {\ln \left( -1+y \left( x \right) \right) y \left( x \right) }{ \left( 1-y \left( x \right) \right) \ln \left( x \right) x}}-{\frac {\ln \left( -1+y \left( x \right) \right) }{ \left( 1-y \left( x \right) \right) \ln \left( x \right) x}}-f \left( x \right) \right) \left( 1-y \left( x \right) \right) =0} \]