let T be TopSpace; OPD-Meet T = (D-Meet T) || (Open_Domains_of T)
A1:
Open_Domains_of T c= Domains_of T
by Th35;
then reconsider F = OPD-Meet T as Function of [:(Open_Domains_of T),(Open_Domains_of T):],(Domains_of T) by FUNCT_2:7;
[:(Open_Domains_of T),(Open_Domains_of T):] c= [:(Domains_of T),(Domains_of T):]
by A1, ZFMISC_1:96;
then reconsider G = (D-Meet T) || (Open_Domains_of T) as Function of [:(Open_Domains_of T),(Open_Domains_of T):],(Domains_of T) by FUNCT_2:32;
for A, B being Element of Open_Domains_of T holds F . (A,B) = G . (A,B)
hence
OPD-Meet T = (D-Meet T) || (Open_Domains_of T)
by BINOP_1:2; verum