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 )
assume A2: ( f in x & g in y ) ; :: thesis: f + g in x + y
reconsider x1 = x, y1 = y as Point of (Pre-L-Space M) ;
x1 in the carrier of (Pre-L-Space M) ;
then A3: x1 in CosetSet M by VSPDef6X;
then consider a being PartFunc of X,REAL such that
A4: ( x1 = a.e-eq-class a,M & a in L1_Functions M ) ;
A5: a in x1 by A4, EQC01;
y1 in the carrier of (Pre-L-Space M) ;
then A6: y1 in CosetSet M by VSPDef6X;
then consider b being PartFunc of X,REAL such that
A7: ( y1 = a.e-eq-class b,M & b in L1_Functions M ) ;
b in y1 by A7, EQC01;
then (addCoset M) . x1,y1 = a.e-eq-class (a + b),M by A3, A6, A5, VSPDef3X;
then A9: x1 + y1 = a.e-eq-class (a + b),M by VSPDef6X;
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 A2, A4;
then A11: a.e-eq-class a,M = a.e-eq-class f,M by EQC02;
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, A7;
then a.e-eq-class b,M = a.e-eq-class g,M by EQC02;
then a.e-eq-class (a + b),M = a.e-eq-class (f + g),M by A2, A4, A7, A11, EQC03;
hence f + g in x + y by EQC01, A9, Th01a, A4, A2, A7; :: thesis: verum
end;
hereby :: thesis: verum
assume A15: f in x ; :: thesis: a (#) f in a * x
reconsider x1 = x as Point of (Pre-L-Space M) ;
x1 in the carrier of (Pre-L-Space M) ;
then A16: x1 in CosetSet M by VSPDef6X;
then consider f1 being PartFunc of X,REAL such that
A17: ( x1 = a.e-eq-class f1,M & f1 in L1_Functions M ) ;
f1 in x1 by A17, EQC01;
then (lmultCoset M) . a,x1 = a.e-eq-class (a (#) f1),M by A16, VSPDef5X;
then A19: a * x1 = a.e-eq-class (a (#) f1),M by VSPDef6X;
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 A15, A17;
then a.e-eq-class f1,M = a.e-eq-class f,M by EQC02;
then a.e-eq-class (a (#) f1),M = a.e-eq-class (a (#) f),M by A17, A15, EQC04;
hence a (#) f in a * x by A19, Th01b, A15, A17, EQC01; :: thesis: verum
end;