Metamath Proof Explorer


Theorem measinblem

Description: Lemma for measinb . (Contributed by Thierry Arnoux, 2-Jun-2017)

Ref Expression
Assertion measinblem
|- ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> ( M ` ( U. B i^i A ) ) = sum* x e. B ( M ` ( x i^i A ) ) )

Proof

Step Hyp Ref Expression
1 iunin1
 |-  U_ x e. B ( x i^i A ) = ( U_ x e. B x i^i A )
2 uniiun
 |-  U. B = U_ x e. B x
3 2 ineq1i
 |-  ( U. B i^i A ) = ( U_ x e. B x i^i A )
4 1 3 eqtr4i
 |-  U_ x e. B ( x i^i A ) = ( U. B i^i A )
5 4 fveq2i
 |-  ( M ` U_ x e. B ( x i^i A ) ) = ( M ` ( U. B i^i A ) )
6 simplll
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> M e. ( measures ` S ) )
7 nfv
 |-  F/ x ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S )
8 nfv
 |-  F/ x B ~<_ _om
9 nfdisj1
 |-  F/ x Disj_ x e. B x
10 8 9 nfan
 |-  F/ x ( B ~<_ _om /\ Disj_ x e. B x )
11 7 10 nfan
 |-  F/ x ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) )
12 simp1ll
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> M e. ( measures ` S ) )
13 measbase
 |-  ( M e. ( measures ` S ) -> S e. U. ran sigAlgebra )
14 12 13 syl
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> S e. U. ran sigAlgebra )
15 simp3
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> x e. B )
16 simp1r
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> B e. ~P S )
17 elelpwi
 |-  ( ( x e. B /\ B e. ~P S ) -> x e. S )
18 15 16 17 syl2anc
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> x e. S )
19 simp1lr
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> A e. S )
20 inelsiga
 |-  ( ( S e. U. ran sigAlgebra /\ x e. S /\ A e. S ) -> ( x i^i A ) e. S )
21 14 18 19 20 syl3anc
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) /\ x e. B ) -> ( x i^i A ) e. S )
22 21 3expia
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> ( x e. B -> ( x i^i A ) e. S ) )
23 11 22 ralrimi
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> A. x e. B ( x i^i A ) e. S )
24 simprl
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> B ~<_ _om )
25 disjin
 |-  ( Disj_ x e. B x -> Disj_ x e. B ( x i^i A ) )
26 25 ad2antll
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> Disj_ x e. B ( x i^i A ) )
27 measvuni
 |-  ( ( M e. ( measures ` S ) /\ A. x e. B ( x i^i A ) e. S /\ ( B ~<_ _om /\ Disj_ x e. B ( x i^i A ) ) ) -> ( M ` U_ x e. B ( x i^i A ) ) = sum* x e. B ( M ` ( x i^i A ) ) )
28 6 23 24 26 27 syl112anc
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> ( M ` U_ x e. B ( x i^i A ) ) = sum* x e. B ( M ` ( x i^i A ) ) )
29 5 28 eqtr3id
 |-  ( ( ( ( M e. ( measures ` S ) /\ A e. S ) /\ B e. ~P S ) /\ ( B ~<_ _om /\ Disj_ x e. B x ) ) -> ( M ` ( U. B i^i A ) ) = sum* x e. B ( M ` ( x i^i A ) ) )