let C1, C2, C3 be non empty set ; :: thesis: for f, g being RMembership_Func of C1,C2
for h being RMembership_Func of C2,C3
for x, z being set st x in C1 & z in C3 holds
sup (rng (min (max f,g),h,x,z)) = max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))

let f, g be RMembership_Func of C1,C2; :: thesis: for h being RMembership_Func of C2,C3
for x, z being set st x in C1 & z in C3 holds
sup (rng (min (max f,g),h,x,z)) = max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))

let h be RMembership_Func of C2,C3; :: thesis: for x, z being set st x in C1 & z in C3 holds
sup (rng (min (max f,g),h,x,z)) = max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))

let x, z be set ; :: thesis: ( x in C1 & z in C3 implies sup (rng (min (max f,g),h,x,z)) = max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) )
assume A1: ( x in C1 & z in C3 ) ; :: thesis: sup (rng (min (max f,g),h,x,z)) = max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))
A2: min (max f,g),h,x,z = max (min f,h,x,z),(min g,h,x,z)
proof
A3: ( dom (min (max f,g),h,x,z) = C2 & dom (max (min f,h,x,z),(min g,h,x,z)) = C2 ) by FUNCT_2:def 1;
for y being Element of C2 st y in C2 holds
(min (max f,g),h,x,z) . y = (max (min f,h,x,z),(min g,h,x,z)) . y
proof
let y be Element of C2; :: thesis: ( y in C2 implies (min (max f,g),h,x,z) . y = (max (min f,h,x,z),(min g,h,x,z)) . y )
assume y in C2 ; :: thesis: (min (max f,g),h,x,z) . y = (max (min f,h,x,z),(min g,h,x,z)) . y
A4: [x,y] in [:C1,C2:] by A1, ZFMISC_1:106;
(min (max f,g),h,x,z) . y = min ((max f,g) . [x,y]),(h . [y,z]) by A1, Def2
.= min (max (f . [x,y]),(g . [x,y])),(h . [y,z]) by A4, FUZZY_1:def 5
.= max (min (f . [x,y]),(h . [y,z])),(min (g . [x,y]),(h . [y,z])) by XXREAL_0:38
.= max (min (f . [x,y]),(h . [y,z])),((min g,h,x,z) . y) by A1, Def2
.= max ((min f,h,x,z) . y),((min g,h,x,z) . y) by A1, Def2 ;
hence (min (max f,g),h,x,z) . y = (max (min f,h,x,z),(min g,h,x,z)) . y by FUZZY_1:def 5; :: thesis: verum
end;
hence min (max f,g),h,x,z = max (min f,h,x,z),(min g,h,x,z) by A3, PARTFUN1:34; :: thesis: verum
end;
set F = min f,h,x,z;
set G = min g,h,x,z;
rng (max (min f,h,x,z),(min g,h,x,z)) is bounded by Th1;
then A5: rng (max (min f,h,x,z),(min g,h,x,z)) is bounded_above by XXREAL_2:def 11;
rng (min f,h,x,z) is bounded by Th1;
then A6: rng (min f,h,x,z) is bounded_above by XXREAL_2:def 11;
rng (min g,h,x,z) is bounded by Th1;
then A7: rng (min g,h,x,z) is bounded_above by XXREAL_2:def 11;
A8: for y being set st y in dom (min f,h,x,z) holds
(min f,h,x,z) . y <= sup (rng (min f,h,x,z))
proof
let y be set ; :: thesis: ( y in dom (min f,h,x,z) implies (min f,h,x,z) . y <= sup (rng (min f,h,x,z)) )
assume y in dom (min f,h,x,z) ; :: thesis: (min f,h,x,z) . y <= sup (rng (min f,h,x,z))
then (min f,h,x,z) . y in rng (min f,h,x,z) by FUNCT_1:def 5;
hence (min f,h,x,z) . y <= sup (rng (min f,h,x,z)) by A6, SEQ_4:def 4; :: thesis: verum
end;
A9: for y being set st y in dom (min g,h,x,z) holds
(min g,h,x,z) . y <= sup (rng (min g,h,x,z))
proof
let y be set ; :: thesis: ( y in dom (min g,h,x,z) implies (min g,h,x,z) . y <= sup (rng (min g,h,x,z)) )
assume y in dom (min g,h,x,z) ; :: thesis: (min g,h,x,z) . y <= sup (rng (min g,h,x,z))
then (min g,h,x,z) . y in rng (min g,h,x,z) by FUNCT_1:def 5;
hence (min g,h,x,z) . y <= sup (rng (min g,h,x,z)) by A7, SEQ_4:def 4; :: thesis: verum
end;
A10: for y being set st y in dom (max (min f,h,x,z),(min g,h,x,z)) holds
(max (min f,h,x,z),(min g,h,x,z)) . y <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
proof
let y be set ; :: thesis: ( y in dom (max (min f,h,x,z),(min g,h,x,z)) implies (max (min f,h,x,z),(min g,h,x,z)) . y <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) )
assume y in dom (max (min f,h,x,z),(min g,h,x,z)) ; :: thesis: (max (min f,h,x,z),(min g,h,x,z)) . y <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
then (max (min f,h,x,z),(min g,h,x,z)) . y in rng (max (min f,h,x,z),(min g,h,x,z)) by FUNCT_1:def 5;
hence (max (min f,h,x,z),(min g,h,x,z)) . y <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by A5, SEQ_4:def 4; :: thesis: verum
end;
A11: sup (rng (max (min f,h,x,z),(min g,h,x,z))) <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))
proof
for s being real number st 0 < s holds
(sup (rng (max (min f,h,x,z),(min g,h,x,z)))) - s <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))
proof
let s be real number ; :: thesis: ( 0 < s implies (sup (rng (max (min f,h,x,z),(min g,h,x,z)))) - s <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) )
assume 0 < s ; :: thesis: (sup (rng (max (min f,h,x,z),(min g,h,x,z)))) - s <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))
then consider r being real number such that
A12: ( r in rng (max (min f,h,x,z),(min g,h,x,z)) & (sup (rng (max (min f,h,x,z),(min g,h,x,z)))) - s < r ) by A5, SEQ_4:def 4;
consider y being set such that
A13: ( y in dom (max (min f,h,x,z),(min g,h,x,z)) & r = (max (min f,h,x,z),(min g,h,x,z)) . y ) by A12, FUNCT_1:def 5;
y in C2 by A13;
then ( y in dom (min f,h,x,z) & y in dom (min g,h,x,z) ) by FUNCT_2:def 1;
then ( (min f,h,x,z) . y <= sup (rng (min f,h,x,z)) & (min g,h,x,z) . y <= sup (rng (min g,h,x,z)) ) by A8, A9;
then A14: max ((min f,h,x,z) . y),((min g,h,x,z) . y) <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) by XXREAL_0:26;
(sup (rng (max (min f,h,x,z),(min g,h,x,z)))) - s <= max ((min f,h,x,z) . y),((min g,h,x,z) . y) by A12, A13, FUZZY_1:def 5;
hence (sup (rng (max (min f,h,x,z),(min g,h,x,z)))) - s <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) by A14, XXREAL_0:2; :: thesis: verum
end;
hence sup (rng (max (min f,h,x,z),(min g,h,x,z))) <= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) by XREAL_1:59; :: thesis: verum
end;
sup (rng (max (min f,h,x,z),(min g,h,x,z))) >= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z)))
proof
A15: sup (rng (min f,h,x,z)) <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
proof
A16: for s being real number st 0 < s holds
ex y being set st
( y in dom (min f,h,x,z) & (sup (rng (min f,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y )
proof
let s be real number ; :: thesis: ( 0 < s implies ex y being set st
( y in dom (min f,h,x,z) & (sup (rng (min f,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y ) )

assume 0 < s ; :: thesis: ex y being set st
( y in dom (min f,h,x,z) & (sup (rng (min f,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y )

then consider r being real number such that
A17: ( r in rng (min f,h,x,z) & (sup (rng (min f,h,x,z))) - s < r ) by A6, SEQ_4:def 4;
consider y being set such that
A18: ( y in dom (min f,h,x,z) & r = (min f,h,x,z) . y ) by A17, FUNCT_1:def 5;
(min f,h,x,z) . y <= max ((min f,h,x,z) . y),((min g,h,x,z) . y) by XXREAL_0:25;
then r <= (max (min f,h,x,z),(min g,h,x,z)) . y by A18, FUZZY_1:def 5;
hence ex y being set st
( y in dom (min f,h,x,z) & (sup (rng (min f,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y ) by A17, A18, XXREAL_0:2; :: thesis: verum
end;
for s being real number st 0 < s holds
(sup (rng (min f,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
proof
let s be real number ; :: thesis: ( 0 < s implies (sup (rng (min f,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) )
assume 0 < s ; :: thesis: (sup (rng (min f,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
then consider y being set such that
A19: ( y in dom (min f,h,x,z) & (sup (rng (min f,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y ) by A16;
y in C2 by A19;
then y in dom (max (min f,h,x,z),(min g,h,x,z)) by FUNCT_2:def 1;
then (max (min f,h,x,z),(min g,h,x,z)) . y <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by A10;
hence (sup (rng (min f,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by A19, XXREAL_0:2; :: thesis: verum
end;
hence sup (rng (min f,h,x,z)) <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by XREAL_1:59; :: thesis: verum
end;
sup (rng (min g,h,x,z)) <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
proof
A20: for s being real number st 0 < s holds
ex y being set st
( y in dom (min g,h,x,z) & (sup (rng (min g,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y )
proof
let s be real number ; :: thesis: ( 0 < s implies ex y being set st
( y in dom (min g,h,x,z) & (sup (rng (min g,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y ) )

assume 0 < s ; :: thesis: ex y being set st
( y in dom (min g,h,x,z) & (sup (rng (min g,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y )

then consider r being real number such that
A21: ( r in rng (min g,h,x,z) & (sup (rng (min g,h,x,z))) - s < r ) by A7, SEQ_4:def 4;
consider y being set such that
A22: ( y in dom (min g,h,x,z) & r = (min g,h,x,z) . y ) by A21, FUNCT_1:def 5;
(min g,h,x,z) . y <= max ((min f,h,x,z) . y),((min g,h,x,z) . y) by XXREAL_0:25;
then r <= (max (min f,h,x,z),(min g,h,x,z)) . y by A22, FUZZY_1:def 5;
hence ex y being set st
( y in dom (min g,h,x,z) & (sup (rng (min g,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y ) by A21, A22, XXREAL_0:2; :: thesis: verum
end;
for s being real number st 0 < s holds
(sup (rng (min g,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
proof
let s be real number ; :: thesis: ( 0 < s implies (sup (rng (min g,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) )
assume 0 < s ; :: thesis: (sup (rng (min g,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z)))
then consider y being set such that
A23: ( y in dom (min g,h,x,z) & (sup (rng (min g,h,x,z))) - s <= (max (min f,h,x,z),(min g,h,x,z)) . y ) by A20;
y in C2 by A23;
then y in dom (max (min f,h,x,z),(min g,h,x,z)) by FUNCT_2:def 1;
then (max (min f,h,x,z),(min g,h,x,z)) . y <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by A10;
hence (sup (rng (min g,h,x,z))) - s <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by A23, XXREAL_0:2; :: thesis: verum
end;
hence sup (rng (min g,h,x,z)) <= sup (rng (max (min f,h,x,z),(min g,h,x,z))) by XREAL_1:59; :: thesis: verum
end;
hence sup (rng (max (min f,h,x,z),(min g,h,x,z))) >= max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) by A15, XXREAL_0:28; :: thesis: verum
end;
hence sup (rng (min (max f,g),h,x,z)) = max (sup (rng (min f,h,x,z))),(sup (rng (min g,h,x,z))) by A2, A11, XXREAL_0:1; :: thesis: verum