let X be non empty set ; for S being SigmaField of X
for f being PartFunc of X,ExtREAL
for A being Element of S
for r, s being Real st f is_measurable_on A & A c= dom f holds
(A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S
let S be SigmaField of X; for f being PartFunc of X,ExtREAL
for A being Element of S
for r, s being Real st f is_measurable_on A & A c= dom f holds
(A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S
let f be PartFunc of X,ExtREAL ; for A being Element of S
for r, s being Real st f is_measurable_on A & A c= dom f holds
(A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S
let A be Element of S; for r, s being Real st f is_measurable_on A & A c= dom f holds
(A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S
let r, s be Real; ( f is_measurable_on A & A c= dom f implies (A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S )
assume that
A1:
f is_measurable_on A
and
A2:
A c= dom f
; (A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S
A3:
A /\ (less_dom f,(R_EAL s)) in S
by A1, MESFUNC1:def 17;
A4: (A /\ (great_eq_dom f,(R_EAL r))) /\ (A /\ (less_dom f,(R_EAL s))) =
((A /\ (great_eq_dom f,(R_EAL r))) /\ A) /\ (less_dom f,(R_EAL s))
by XBOOLE_1:16
.=
((great_eq_dom f,(R_EAL r)) /\ (A /\ A)) /\ (less_dom f,(R_EAL s))
by XBOOLE_1:16
;
A /\ (great_eq_dom f,(R_EAL r)) in S
by A1, A2, MESFUNC1:31;
hence
(A /\ (great_eq_dom f,(R_EAL r))) /\ (less_dom f,(R_EAL s)) in S
by A3, A4, FINSUB_1:def 2; verum