set N = Net-Str S,f;
netmap (Net-Str S,f),R is monotone
proof
let x,
y be
Element of
(Net-Str S,f);
WAYBEL_1:def 2 ( not x <= y or (netmap (Net-Str S,f),R) . x <= (netmap (Net-Str S,f),R) . y )
A1:
(netmap (Net-Str S,f),R) . x = (Net-Str S,f) . x
;
A2:
(netmap (Net-Str S,f),R) . y = (Net-Str S,f) . y
;
assume
x <= y
;
(netmap (Net-Str S,f),R) . x <= (netmap (Net-Str S,f),R) . y
hence
(netmap (Net-Str S,f),R) . x <= (netmap (Net-Str S,f),R) . y
by A1, A2, Def10;
verum
end;
hence
Net-Str S,f is monotone
by WAYBEL_0:def 9; verum