Funktionen
\[\frac{-\left(x^2-1\right) \left(y^2-4\right)-x^2-y^2+5}{\left(x^2+y^2+1\right)^2}\]
Partialderivata
\[\frac{2 x \left(x^2 \left(y^2-3\right)-y^4+2 y^2+1\right)}{\left(x^2+y^2+1\right)^3}\]
\[-\frac{2 y \left(x^4-x^2 \left(y^2-7\right)+2\right)}{\left(x^2+y^2+1\right)^3}\]
Mvh // Karin Söderlund