let X be non empty set ; for S being SigmaField of X
for M being sigma_Measure of S
for f, g, f1, g1 being PartFunc of X,REAL
for k being positive Real st ex E being Element of S st
( M . (E `) = 0 & E = dom f & f is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom f1 & f1 is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g & g is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g1 & g1 is E -measurable ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds
a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k)
let S be SigmaField of X; for M being sigma_Measure of S
for f, g, f1, g1 being PartFunc of X,REAL
for k being positive Real st ex E being Element of S st
( M . (E `) = 0 & E = dom f & f is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom f1 & f1 is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g & g is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g1 & g1 is E -measurable ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds
a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k)
let M be sigma_Measure of S; for f, g, f1, g1 being PartFunc of X,REAL
for k being positive Real st ex E being Element of S st
( M . (E `) = 0 & E = dom f & f is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom f1 & f1 is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g & g is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g1 & g1 is E -measurable ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds
a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k)
let f, g, f1, g1 be PartFunc of X,REAL; for k being positive Real st ex E being Element of S st
( M . (E `) = 0 & E = dom f & f is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom f1 & f1 is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g & g is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g1 & g1 is E -measurable ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds
a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k)
let k be positive Real; ( ex E being Element of S st
( M . (E `) = 0 & E = dom f & f is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom f1 & f1 is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g & g is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g1 & g1 is E -measurable ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) implies a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) )
assume
( ex E being Element of S st
( M . (E `) = 0 & E = dom f & f is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom f1 & f1 is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g & g is E -measurable ) & ex E being Element of S st
( M . (E `) = 0 & E = dom g1 & g1 is E -measurable ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) )
; a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k)
then
( f a.e.= f1,M & g a.e.= g1,M )
by Th39;
hence
a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k)
by Th41, LPSPACE1:31; verum