let a be Real; :: thesis: for X being non empty set
for S being SigmaField of X
for M being sigma_Measure of S
for f, g being PartFunc of X,REAL
for x, y being Point of (L-1-Space M) holds
( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) )

let X be non empty set ; :: thesis: for S being SigmaField of X
for M being sigma_Measure of S
for f, g being PartFunc of X,REAL
for x, y being Point of (L-1-Space M) holds
( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) )

let S be SigmaField of X; :: thesis: for M being sigma_Measure of S
for f, g being PartFunc of X,REAL
for x, y being Point of (L-1-Space M) holds
( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) )

let M be sigma_Measure of S; :: thesis: for f, g being PartFunc of X,REAL
for x, y being Point of (L-1-Space M) holds
( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) )

let f, g be PartFunc of X,REAL; :: thesis: for x, y being Point of (L-1-Space M) holds
( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) )

let x, y be Point of (L-1-Space M); :: thesis: ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) )
set C = CosetSet M;
hereby :: thesis: ( f in x implies a (#) f in a * x )
reconsider x1 = x, y1 = y as Point of (Pre-L-Space M) ;
assume that
A1: f in x and
A2: g in y ; :: thesis: f + g in x + y
y1 in the carrier of (Pre-L-Space M) ;
then A3: y1 in CosetSet M by Def18;
then consider b being PartFunc of X,REAL such that
A4: y1 = a.e-eq-class (b,M) and
A5: b in L1_Functions M ;
A6: b in y1 by A4, A5, Th38;
ex r being PartFunc of X,REAL st
( g = r & r in L1_Functions M & b in L1_Functions M & b a.e.= r,M ) by A2, A4;
then A7: a.e-eq-class (b,M) = a.e-eq-class (g,M) by Th39;
x1 in the carrier of (Pre-L-Space M) ;
then A8: x1 in CosetSet M by Def18;
then consider a being PartFunc of X,REAL such that
A9: x1 = a.e-eq-class (a,M) and
A10: a in L1_Functions M ;
a in x1 by A9, A10, Th38;
then (addCoset M) . (x1,y1) = a.e-eq-class ((a + b),M) by A8, A3, A6, Def15;
then A11: x1 + y1 = a.e-eq-class ((a + b),M) by Def18;
ex r being PartFunc of X,REAL st
( f = r & r in L1_Functions M & a in L1_Functions M & a a.e.= r,M ) by A1, A9;
then a.e-eq-class (a,M) = a.e-eq-class (f,M) by Th39;
then a.e-eq-class ((a + b),M) = a.e-eq-class ((f + g),M) by A1, A2, A9, A10, A4, A5, A7, Th41;
hence f + g in x + y by A1, A2, A9, A4, A11, Th23, Th38; :: thesis: verum
end;
hereby :: thesis: verum
reconsider x1 = x as Point of (Pre-L-Space M) ;
x1 in the carrier of (Pre-L-Space M) ;
then A12: x1 in CosetSet M by Def18;
then consider f1 being PartFunc of X,REAL such that
A13: x1 = a.e-eq-class (f1,M) and
A14: f1 in L1_Functions M ;
f1 in x1 by A13, A14, Th38;
then (lmultCoset M) . (a,x1) = a.e-eq-class ((a (#) f1),M) by A12, Def17;
then A15: a * x1 = a.e-eq-class ((a (#) f1),M) by Def18;
assume A16: f in x ; :: thesis: a (#) f in a * x
then ex r being PartFunc of X,REAL st
( f = r & r in L1_Functions M & f1 in L1_Functions M & f1 a.e.= r,M ) by A13;
then a.e-eq-class (f1,M) = a.e-eq-class (f,M) by Th39;
then a.e-eq-class ((a (#) f1),M) = a.e-eq-class ((a (#) f),M) by A16, A13, A14, Th42;
hence a (#) f in a * x by A16, A13, A15, Th24, Th38; :: thesis: verum
end;