funcions neutre-expansives

Si f(x) = max{z€A: x [< z+x } ==> 0 [< f(x)

x [< z+x [< max{z€A: x [< z+x }+x = f(x)+x

Si f(x) = min{z€A: x >] z+x } ==> 0 >] f(x)

Si f(x) = max{z€A: 0 < x & x [< z·x } ==> 1 [< f(x)

x [< z·x [< max{z€A: x [< z·x }·x = f(x)·x

Si f(x) = min{z€A: 0 < x & x >] z·x } ==> 1 >] f(x)

Si f(x) = min{z€A: 0 > x & x [< z·x } ==> 1 [< f(x)

x [< z·x [< min{z€A: x [< z·x }·x = f(x)·x

Si f(x) = max{z€A: 0 > x & x >] z·x } ==> 1 >] f(x)