Metamath Proof Explorer


Theorem imasdsval

Description: The distance function of an image structure. (Contributed by Mario Carneiro, 20-Aug-2015) (Revised by AV, 6-Oct-2020)

Ref Expression
Hypotheses imasbas.u φU=F𝑠R
imasbas.v φV=BaseR
imasbas.f φF:VontoB
imasbas.r φRZ
imasds.e E=distR
imasds.d D=distU
imasdsval.x φXB
imasdsval.y φYB
imasdsval.s S=hV×V1n|F1sth1=XF2ndhn=Yi1n1F2ndhi=F1sthi+1
Assertion imasdsval φXDY=supnrangS𝑠*Eg*<

Proof

Step Hyp Ref Expression
1 imasbas.u φU=F𝑠R
2 imasbas.v φV=BaseR
3 imasbas.f φF:VontoB
4 imasbas.r φRZ
5 imasds.e E=distR
6 imasds.d D=distU
7 imasdsval.x φXB
8 imasdsval.y φYB
9 imasdsval.s S=hV×V1n|F1sth1=XF2ndhn=Yi1n1F2ndhi=F1sthi+1
10 1 2 3 4 5 6 imasds φD=xB,yBsupnranghV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1𝑠*Eg*<
11 simplrl φx=Xy=Ynx=X
12 11 eqeq2d φx=Xy=YnF1sth1=xF1sth1=X
13 simplrr φx=Xy=Yny=Y
14 13 eqeq2d φx=Xy=YnF2ndhn=yF2ndhn=Y
15 12 14 3anbi12d φx=Xy=YnF1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1F1sth1=XF2ndhn=Yi1n1F2ndhi=F1sthi+1
16 15 rabbidv φx=Xy=YnhV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1=hV×V1n|F1sth1=XF2ndhn=Yi1n1F2ndhi=F1sthi+1
17 16 9 eqtr4di φx=Xy=YnhV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1=S
18 17 mpteq1d φx=Xy=YnghV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1𝑠*Eg=gS𝑠*Eg
19 18 rneqd φx=Xy=YnranghV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1𝑠*Eg=rangS𝑠*Eg
20 19 iuneq2dv φx=Xy=YnranghV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1𝑠*Eg=nrangS𝑠*Eg
21 20 infeq1d φx=Xy=YsupnranghV×V1n|F1sth1=xF2ndhn=yi1n1F2ndhi=F1sthi+1𝑠*Eg*<=supnrangS𝑠*Eg*<
22 xrltso <Or*
23 22 infex supnrangS𝑠*Eg*<V
24 23 a1i φsupnrangS𝑠*Eg*<V
25 10 21 7 8 24 ovmpod φXDY=supnrangS𝑠*Eg*<