theorem Th18: :: FUZZY_4:18

for C1, C2, C3 being non empty set
for f, g being RMembership_Func of C1,C2
for h, k being RMembership_Func of C2,C3
for x, z being set st x in C1 & z in C3 & ( for y being set st y in C2 holds
( f . [x,y] <= g . [x,y] & h . [y,z] <= k . [y,z] ) ) holds
(f (#) h) . [x,z] <= (g (#) k) . [x,z]