(∂z/∂x)^2+(∂z/∂y)^3+1=1/(z-1)^2
f=(p^2+q^2+1)(z-1)^2-1=0
dx/2p(z-1)^2=dy/2q(z-1)^2
=dz/2p^2(z-1)^2+2q^2(z-1)^2
=dp/-p2(z-1)(p^2+q^2+1)
=dq/-2q(z-1)(p^2+q^2+1)
dp/p=dq/q
q=ap
p=+1/√a^2+1・√2z-z^2/(z-1)
dz=+-1/√a^2+1・√2z-z^2/(z-1)dx+-a/√a^2+1・√2z-z^2/(z-1)dy
dz+-√a^2+1・(z-1)/√2z-z^2=dx+ady
+-√a^2+1√2z-z^2=x+ay+b
--\u0026gt;
(a^2+1)(2z-z^2)=(x+ay+b)^2
