Metamath Proof Explorer


Theorem caragenel2d

Description: Membership in the Caratheodory's construction. Similar to carageneld , but here "less then or equal to" is used, instead of equality. This is Remark 113D of Fremlin1 p. 21. (Contributed by Glauco Siliprandi, 24-Dec-2020)

Ref Expression
Hypotheses caragenel2d.o
|- ( ph -> O e. OutMeas )
caragenel2d.x
|- X = U. dom O
caragenel2d.s
|- S = ( CaraGen ` O )
caragenel2d.e
|- ( ph -> E e. ~P X )
caragenel2d.a
|- ( ( ph /\ a e. ~P X ) -> ( ( O ` ( a i^i E ) ) +e ( O ` ( a \ E ) ) ) <_ ( O ` a ) )
Assertion caragenel2d
|- ( ph -> E e. S )

Proof

Step Hyp Ref Expression
1 caragenel2d.o
 |-  ( ph -> O e. OutMeas )
2 caragenel2d.x
 |-  X = U. dom O
3 caragenel2d.s
 |-  S = ( CaraGen ` O )
4 caragenel2d.e
 |-  ( ph -> E e. ~P X )
5 caragenel2d.a
 |-  ( ( ph /\ a e. ~P X ) -> ( ( O ` ( a i^i E ) ) +e ( O ` ( a \ E ) ) ) <_ ( O ` a ) )
6 1 adantr
 |-  ( ( ph /\ a e. ~P X ) -> O e. OutMeas )
7 inss1
 |-  ( a i^i E ) C_ a
8 elpwi
 |-  ( a e. ~P X -> a C_ X )
9 7 8 sstrid
 |-  ( a e. ~P X -> ( a i^i E ) C_ X )
10 9 adantl
 |-  ( ( ph /\ a e. ~P X ) -> ( a i^i E ) C_ X )
11 6 2 10 omexrcl
 |-  ( ( ph /\ a e. ~P X ) -> ( O ` ( a i^i E ) ) e. RR* )
12 8 ssdifssd
 |-  ( a e. ~P X -> ( a \ E ) C_ X )
13 12 adantl
 |-  ( ( ph /\ a e. ~P X ) -> ( a \ E ) C_ X )
14 6 2 13 omexrcl
 |-  ( ( ph /\ a e. ~P X ) -> ( O ` ( a \ E ) ) e. RR* )
15 xaddcl
 |-  ( ( ( O ` ( a i^i E ) ) e. RR* /\ ( O ` ( a \ E ) ) e. RR* ) -> ( ( O ` ( a i^i E ) ) +e ( O ` ( a \ E ) ) ) e. RR* )
16 11 14 15 syl2anc
 |-  ( ( ph /\ a e. ~P X ) -> ( ( O ` ( a i^i E ) ) +e ( O ` ( a \ E ) ) ) e. RR* )
17 8 adantl
 |-  ( ( ph /\ a e. ~P X ) -> a C_ X )
18 6 2 17 omexrcl
 |-  ( ( ph /\ a e. ~P X ) -> ( O ` a ) e. RR* )
19 6 2 17 omelesplit
 |-  ( ( ph /\ a e. ~P X ) -> ( O ` a ) <_ ( ( O ` ( a i^i E ) ) +e ( O ` ( a \ E ) ) ) )
20 16 18 5 19 xrletrid
 |-  ( ( ph /\ a e. ~P X ) -> ( ( O ` ( a i^i E ) ) +e ( O ` ( a \ E ) ) ) = ( O ` a ) )
21 1 2 3 4 20 carageneld
 |-  ( ph -> E e. S )