let I, J, K be non empty closed_interval Subset of REAL; for f being PartFunc of [:[:RNS_Real,RNS_Real:],RNS_Real:],RNS_Real
for g being PartFunc of [:[:REAL,REAL:],REAL:],REAL st [:[:I,J:],K:] = dom f & f is_continuous_on [:[:I,J:],K:] & f = g holds
( ( for V being Element of L-Field holds Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is V -measurable ) & Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is_integrable_on L-Meas & Integral ((Prod_Measure (L-Meas,L-Meas)),(Integral2 (L-Meas,(R_EAL g)))) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),g) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])))) )
let f be PartFunc of [:[:RNS_Real,RNS_Real:],RNS_Real:],RNS_Real; for g being PartFunc of [:[:REAL,REAL:],REAL:],REAL st [:[:I,J:],K:] = dom f & f is_continuous_on [:[:I,J:],K:] & f = g holds
( ( for V being Element of L-Field holds Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is V -measurable ) & Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is_integrable_on L-Meas & Integral ((Prod_Measure (L-Meas,L-Meas)),(Integral2 (L-Meas,(R_EAL g)))) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),g) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])))) )
let g be PartFunc of [:[:REAL,REAL:],REAL:],REAL; ( [:[:I,J:],K:] = dom f & f is_continuous_on [:[:I,J:],K:] & f = g implies ( ( for V being Element of L-Field holds Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is V -measurable ) & Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is_integrable_on L-Meas & Integral ((Prod_Measure (L-Meas,L-Meas)),(Integral2 (L-Meas,(R_EAL g)))) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),g) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])))) ) )
assume that
A1:
[:[:I,J:],K:] = dom f
and
A2:
f is_continuous_on [:[:I,J:],K:]
and
A3:
f = g
; ( ( for V being Element of L-Field holds Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is V -measurable ) & Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is_integrable_on L-Meas & Integral ((Prod_Measure (L-Meas,L-Meas)),(Integral2 (L-Meas,(R_EAL g)))) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),g) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])))) )
set RF = Integral2 (L-Meas,(R_EAL g));
A4:
dom (Integral2 (L-Meas,(R_EAL g))) = [:REAL,REAL:]
by FUNCT_2:def 1;
reconsider RG = (Integral2 (L-Meas,(R_EAL g))) | [:I,J:] as PartFunc of [:REAL,REAL:],REAL by A1, A2, A3, Th32;
reconsider RGG = RG as PartFunc of [:RNS_Real,RNS_Real:],RNS_Real ;
A5:
Integral2 (L-Meas,(R_EAL g)) is_integrable_on Prod_Measure (L-Meas,L-Meas)
by A1, A2, A3, Th43;
A6:
for y being Element of REAL holds (Integral1 (L-Meas,|.(Integral2 (L-Meas,(R_EAL g))).|)) . y < +infty
by A1, A2, A3, Th48;
hence
( ( for V being Element of L-Field holds Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is V -measurable ) & Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))) is_integrable_on L-Meas & Integral ((Prod_Measure (L-Meas,L-Meas)),(Integral2 (L-Meas,(R_EAL g)))) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) )
by A5, MESFUN13:33, MESFUN16:5; ( Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),g) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g)))))) & Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])))) )
A7:
g is_integrable_on Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)
by A1, A2, A3, Th43;
for u being Element of [:REAL,REAL:] holds (Integral2 (L-Meas,|.(R_EAL g).|)) . u < +infty
by A1, A2, A3, Th40;
then
Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),(R_EAL g)) = Integral ((Prod_Measure (L-Meas,L-Meas)),(Integral2 (L-Meas,(R_EAL g))))
by A7, MESFUN13:32, MESFUN16:5, MESFUN16:6;
hence
Integral ((Prod_Measure ((Prod_Measure (L-Meas,L-Meas)),L-Meas)),g) = Integral (L-Meas,(Integral1 (L-Meas,(Integral2 (L-Meas,(R_EAL g))))))
by A5, A6, MESFUN13:33, MESFUN16:5; Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:]))))
A8:
(Integral2 (L-Meas,(R_EAL g))) | [:I,J:] = R_EAL RG
by MESFUNC5:def 7;
RGG is_uniformly_continuous_on [:I,J:]
by A1, A2, A3, Th34;
then
RGG is_continuous_on [:I,J:]
by NFCONT_2:7;
then
( RG is_integrable_on Prod_Measure (L-Meas,L-Meas) & Integral ((Prod_Measure (L-Meas,L-Meas)),RG) = Integral (L-Meas,(Integral1 (L-Meas,(R_EAL RG)))) )
by A4, MESFUN16:57;
hence
Integral ((Prod_Measure (L-Meas,L-Meas)),((Integral2 (L-Meas,(R_EAL g))) | [:I,J:])) = Integral (L-Meas,(Integral1 (L-Meas,((Integral2 (L-Meas,(R_EAL g))) | [:I,J:]))))
by A8; verum