theorem Th62: :: MESFUNC6:62
for X being non empty set
for f, g being PartFunc of X,REAL holds
( dom ((max+ (f + g)) + (max- f)) = (dom f) /\ (dom g) & dom ((max- (f + g)) + (max+ f)) = (dom f) /\ (dom g) & dom (((max+ (f + g)) + (max- f)) + (max- g)) = (dom f) /\ (dom g) & dom (((max- (f + g)) + (max+ f)) + (max+ g)) = (dom f) /\ (dom g) & (max+ (f + g)) + (max- f) is nonnegative & (max- (f + g)) + (max+ f) is nonnegative )