let X1, X2 be non empty set ; for S1 being SigmaField of X1
for S2 being SigmaField of X2
for M1 being sigma_Measure of S1
for y being Element of X2
for E being Element of sigma (measurable_rectangles (S1,S2)) st M1 is sigma_finite holds
(X-vol (E,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (E,y)),X1)))
let S1 be SigmaField of X1; for S2 being SigmaField of X2
for M1 being sigma_Measure of S1
for y being Element of X2
for E being Element of sigma (measurable_rectangles (S1,S2)) st M1 is sigma_finite holds
(X-vol (E,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (E,y)),X1)))
let S2 be SigmaField of X2; for M1 being sigma_Measure of S1
for y being Element of X2
for E being Element of sigma (measurable_rectangles (S1,S2)) st M1 is sigma_finite holds
(X-vol (E,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (E,y)),X1)))
let M1 be sigma_Measure of S1; for y being Element of X2
for E being Element of sigma (measurable_rectangles (S1,S2)) st M1 is sigma_finite holds
(X-vol (E,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (E,y)),X1)))
let y be Element of X2; for E being Element of sigma (measurable_rectangles (S1,S2)) st M1 is sigma_finite holds
(X-vol (E,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (E,y)),X1)))
let A be Element of sigma (measurable_rectangles (S1,S2)); ( M1 is sigma_finite implies (X-vol (A,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (A,y)),X1))) )
assume
M1 is sigma_finite
; (X-vol (A,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (A,y)),X1)))
then
(X-vol (A,M1)) . y = M1 . (Measurable-Y-section (A,y))
by MEASUR11:def 14;
hence
(X-vol (A,M1)) . y = Integral (M1,(chi ((Measurable-Y-section (A,y)),X1)))
by MESFUNC9:14; verum