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Description: The distance function of a constructed metric space. (Contributed by Mario Carneiro, 28-Aug-2015) (Proof shortened by AV, 11-Nov-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | setsms.x | |- ( ph -> X = ( Base ` M ) ) |
|
| setsms.d | |- ( ph -> D = ( ( dist ` M ) |` ( X X. X ) ) ) |
||
| setsms.k | |- ( ph -> K = ( M sSet <. ( TopSet ` ndx ) , ( MetOpen ` D ) >. ) ) |
||
| Assertion | setsmsds | |- ( ph -> ( dist ` M ) = ( dist ` K ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | setsms.x | |- ( ph -> X = ( Base ` M ) ) |
|
| 2 | setsms.d | |- ( ph -> D = ( ( dist ` M ) |` ( X X. X ) ) ) |
|
| 3 | setsms.k | |- ( ph -> K = ( M sSet <. ( TopSet ` ndx ) , ( MetOpen ` D ) >. ) ) |
|
| 4 | dsid | |- dist = Slot ( dist ` ndx ) |
|
| 5 | dsndxntsetndx | |- ( dist ` ndx ) =/= ( TopSet ` ndx ) |
|
| 6 | 4 5 | setsnid | |- ( dist ` M ) = ( dist ` ( M sSet <. ( TopSet ` ndx ) , ( MetOpen ` D ) >. ) ) |
| 7 | 3 | fveq2d | |- ( ph -> ( dist ` K ) = ( dist ` ( M sSet <. ( TopSet ` ndx ) , ( MetOpen ` D ) >. ) ) ) |
| 8 | 6 7 | eqtr4id | |- ( ph -> ( dist ` M ) = ( dist ` K ) ) |