Цитата(japan @ 14.3.2009, 4:22) *

Z'x=(y^2/3)+(y/(1-(xy)^2)^1/2)
Z'y=(2y/3x)+(x/(1-(xy)^2)^1/2)

Z'x=(-y^2/3x^2)+(y/(1-(xy)^2)^1/2)