deffunc H₁( Element of Open_Domains_of T, Element of Open_Domains_of T) -> Element of bool the carrier of T = $1 /\ $2;
thus for o1, o2 being BinOp of (Open_Domains_of T) st ( for a, b being Element of Open_Domains_of T holds o1 . (a,b) = H₁(a,b) ) & ( for a, b being Element of Open_Domains_of T holds o2 . (a,b) = H₁(a,b) ) holds
o1 = o2 from BINOP_2:sch 2(); :: thesis: verum