Metamath Proof Explorer


Theorem setsmsds

Description: The distance function of a constructed metric space. (Contributed by Mario Carneiro, 28-Aug-2015)

Ref Expression
Hypotheses setsms.x φ X = Base M
setsms.d φ D = dist M X × X
setsms.k φ K = M sSet TopSet ndx MetOpen D
Assertion setsmsds φ dist M = dist K

Proof

Step Hyp Ref Expression
1 setsms.x φ X = Base M
2 setsms.d φ D = dist M X × X
3 setsms.k φ K = M sSet TopSet ndx MetOpen D
4 3 fveq2d φ dist K = dist M sSet TopSet ndx MetOpen D
5 dsid dist = Slot dist ndx
6 9re 9
7 1nn 1
8 2nn0 2 0
9 9nn0 9 0
10 9lt10 9 < 10
11 7 8 9 10 declti 9 < 12
12 6 11 gtneii 12 9
13 dsndx dist ndx = 12
14 tsetndx TopSet ndx = 9
15 13 14 neeq12i dist ndx TopSet ndx 12 9
16 12 15 mpbir dist ndx TopSet ndx
17 5 16 setsnid dist M = dist M sSet TopSet ndx MetOpen D
18 4 17 syl6reqr φ dist M = dist K