Partialderivatan m.a.p. x
\frac{-2 x\(y^2-4\) -2 x}{\(x^2+y^2+1\)^2}-\frac{4 x\(\(1-x^2\)(y^2-4\)-x^2-y^2+5\)}{\(x^2+y^2+1\)^3}