Metamath Proof Explorer


Theorem ovollb

Description: The outer volume is a lower bound on the sum of all interval coverings of A . (Contributed by Mario Carneiro, 15-Jun-2014)

Ref Expression
Hypothesis ovollb.1 S=seq1+absF
Assertion ovollb F:2Aran.Fvol*AsupranS*<

Proof

Step Hyp Ref Expression
1 ovollb.1 S=seq1+absF
2 simpr F:2Aran.FAran.F
3 ioof .:*×*𝒫
4 simpl F:2Aran.FF:2
5 inss2 22
6 rexpssxrxp 2*×*
7 5 6 sstri 2*×*
8 fss F:22*×*F:*×*
9 4 7 8 sylancl F:2Aran.FF:*×*
10 fco .:*×*𝒫F:*×*.F:𝒫
11 3 9 10 sylancr F:2Aran.F.F:𝒫
12 11 frnd F:2Aran.Fran.F𝒫
13 sspwuni ran.F𝒫ran.F
14 12 13 sylib F:2Aran.Fran.F
15 2 14 sstrd F:2Aran.FA
16 eqid y*|f2Aran.fy=supranseq1+absf*<=y*|f2Aran.fy=supranseq1+absf*<
17 16 ovolval Avol*A=supy*|f2Aran.fy=supranseq1+absf*<*<
18 15 17 syl F:2Aran.Fvol*A=supy*|f2Aran.fy=supranseq1+absf*<*<
19 ssrab2 y*|f2Aran.fy=supranseq1+absf*<*
20 16 1 elovolmr F:2Aran.FsupranS*<y*|f2Aran.fy=supranseq1+absf*<
21 infxrlb y*|f2Aran.fy=supranseq1+absf*<*supranS*<y*|f2Aran.fy=supranseq1+absf*<supy*|f2Aran.fy=supranseq1+absf*<*<supranS*<
22 19 20 21 sylancr F:2Aran.Fsupy*|f2Aran.fy=supranseq1+absf*<*<supranS*<
23 18 22 eqbrtrd F:2Aran.Fvol*AsupranS*<