let X be non empty finite Subset of REAL ; for f being Function of [:X,X:],REAL
for z being non empty finite Subset of REAL
for A being real number st z = rng f & A >= max z holds
(low_toler f,A) [*] = low_toler f,A
let f be Function of [:X,X:],REAL ; for z being non empty finite Subset of REAL
for A being real number st z = rng f & A >= max z holds
(low_toler f,A) [*] = low_toler f,A
let z be non empty finite Subset of REAL ; for A being real number st z = rng f & A >= max z holds
(low_toler f,A) [*] = low_toler f,A
let A be real number ; ( z = rng f & A >= max z implies (low_toler f,A) [*] = low_toler f,A )
assume A1:
( z = rng f & A >= max z )
; (low_toler f,A) [*] = low_toler f,A
now let p be
set ;
( p in (low_toler f,A) [*] implies p in low_toler f,A )assume
p in (low_toler f,A) [*]
;
p in low_toler f,Athen consider x,
y being
set such that A2:
(
x in X &
y in X )
and A3:
p = [x,y]
by ZFMISC_1:def 2;
reconsider x9 =
x,
y9 =
y as
Element of
X by A2;
f . x9,
y9 <= A
by A1, Th26;
hence
p in low_toler f,
A
by A3, Def3;
verum end;
then
( low_toler f,A c= (low_toler f,A) [*] & (low_toler f,A) [*] c= low_toler f,A )
by LANG1:18, TARSKI:def 3;
hence
(low_toler f,A) [*] = low_toler f,A
by XBOOLE_0:def 10; verum