deffunc H1( Real) -> set = 1 - $1;
A1: for a being Element of [.0,1.] holds H1(a) in [.0,1.] by FUZNORM1:7;
ex f being UnOp of [.0,1.] st
for a being Element of [.0,1.] holds f . a = H1(a) from FUNCT_2:sch 8(A1);
hence ex b1 being UnOp of [.0,1.] st
for x being Element of [.0,1.] holds b1 . x = 1 - x ; :: thesis: verum