f(x,y)=(x²+2y)∗(x²+2y)∗(x²+2y)
dxdf(x,y)=2x∗(x²+2y)(x²+2y)+(x²+2y)∗2x∗(x²+2y)+(x²+2y)∗(x²+2y)∗2x
dxdf(x,y)=2x∗(x²+2y)(x²+2y)+2x∗(x²+2y)∗(x²+2y)+2x∗(x²+2y)∗(x²+2y)
dxdf(x,y)=2x∗(x²+2y)(x²+2y)∗[1+1+1]=6x∗(x²+2y)(x²+2y)=6x∗(x²+2y)2
dxdf(x,y)=3∗(x²+2y)2∗2x=6x(x²+2y)2
Das geht doch noch schneller.