Metamath Proof Explorer


Theorem smfpimioompt

Description: Given a function measurable w.r.t. to a sigma-algebra, the preimage of an open interval is in the subspace sigma-algebra induced by its domain. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypotheses smfpimioompt.x xφ
smfpimioompt.s φSSAlg
smfpimioompt.a φAV
smfpimioompt.b φxABW
smfpimioompt.m φxABSMblFnS
smfpimioompt.l φL*
smfpimioompt.r φR*
Assertion smfpimioompt φxA|BLRS𝑡A

Proof

Step Hyp Ref Expression
1 smfpimioompt.x xφ
2 smfpimioompt.s φSSAlg
3 smfpimioompt.a φAV
4 smfpimioompt.b φxABW
5 smfpimioompt.m φxABSMblFnS
6 smfpimioompt.l φL*
7 smfpimioompt.r φR*
8 eqid domxAB=domxAB
9 2 5 8 smff φxAB:domxAB
10 eqid xAB=xAB
11 1 10 4 dmmptdf φdomxAB=A
12 11 feq2d φxAB:domxABxAB:A
13 9 12 mpbid φxAB:A
14 13 fvmptelcdm φxAB
15 14 rexrd φxAB*
16 1 6 7 15 pimiooltgt φxA|BLR=xA|B<RxA|L<B
17 eqid S𝑡A=S𝑡A
18 2 3 17 subsalsal φS𝑡ASAlg
19 1 2 4 5 7 smfpimltxrmpt φxA|B<RS𝑡A
20 1 2 4 5 6 smfpimgtxrmpt φxA|L<BS𝑡A
21 18 19 20 salincld φxA|B<RxA|L<BS𝑡A
22 16 21 eqeltrd φxA|BLRS𝑡A