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Description: Lemma for fpwwe2 . Show by induction that the two isometries M and N agree on their common domain. (Contributed by Mario Carneiro, 15-May-2015) (Proof shortened by Peter Mazsa, 23-Sep-2022) (Revised by AV, 20-Jul-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | fpwwe2.1 | |- W = { <. x , r >. | ( ( x C_ A /\ r C_ ( x X. x ) ) /\ ( r We x /\ A. y e. x [. ( `' r " { y } ) / u ]. ( u F ( r i^i ( u X. u ) ) ) = y ) ) } |
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| fpwwe2.2 | |- ( ph -> A e. V ) |
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| fpwwe2.3 | |- ( ( ph /\ ( x C_ A /\ r C_ ( x X. x ) /\ r We x ) ) -> ( x F r ) e. A ) |
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| fpwwe2lem8.x | |- ( ph -> X W R ) |
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| fpwwe2lem8.y | |- ( ph -> Y W S ) |
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| fpwwe2lem8.m | |- M = OrdIso ( R , X ) |
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| fpwwe2lem8.n | |- N = OrdIso ( S , Y ) |
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| fpwwe2lem8.s | |- ( ph -> dom M C_ dom N ) |
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| Assertion | fpwwe2lem7 | |- ( ph -> M = ( N |` dom M ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fpwwe2.1 | |- W = { <. x , r >. | ( ( x C_ A /\ r C_ ( x X. x ) ) /\ ( r We x /\ A. y e. x [. ( `' r " { y } ) / u ]. ( u F ( r i^i ( u X. u ) ) ) = y ) ) } |
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| 2 | fpwwe2.2 | |- ( ph -> A e. V ) |
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| 3 | fpwwe2.3 | |- ( ( ph /\ ( x C_ A /\ r C_ ( x X. x ) /\ r We x ) ) -> ( x F r ) e. A ) |
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| 4 | fpwwe2lem8.x | |- ( ph -> X W R ) |
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| 5 | fpwwe2lem8.y | |- ( ph -> Y W S ) |
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| 6 | fpwwe2lem8.m | |- M = OrdIso ( R , X ) |
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| 7 | fpwwe2lem8.n | |- N = OrdIso ( S , Y ) |
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| 8 | fpwwe2lem8.s | |- ( ph -> dom M C_ dom N ) |
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| 9 | 6 | oif | |- M : dom M --> X |
| 10 | ffn | |- ( M : dom M --> X -> M Fn dom M ) |
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| 11 | 9 10 | mp1i | |- ( ph -> M Fn dom M ) |
| 12 | 7 | oif | |- N : dom N --> Y |
| 13 | ffn | |- ( N : dom N --> Y -> N Fn dom N ) |
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| 14 | 12 13 | mp1i | |- ( ph -> N Fn dom N ) |
| 15 | 14 8 | fnssresd | |- ( ph -> ( N |` dom M ) Fn dom M ) |
| 16 | 6 | oicl | |- Ord dom M |
| 17 | ordelon | |- ( ( Ord dom M /\ w e. dom M ) -> w e. On ) |
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| 18 | 16 17 | mpan | |- ( w e. dom M -> w e. On ) |
| 19 | eleq1w | |- ( w = y -> ( w e. dom M <-> y e. dom M ) ) |
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| 20 | fveq2 | |- ( w = y -> ( M ` w ) = ( M ` y ) ) |
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| 21 | fveq2 | |- ( w = y -> ( N ` w ) = ( N ` y ) ) |
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| 22 | 20 21 | eqeq12d | |- ( w = y -> ( ( M ` w ) = ( N ` w ) <-> ( M ` y ) = ( N ` y ) ) ) |
| 23 | 19 22 | imbi12d | |- ( w = y -> ( ( w e. dom M -> ( M ` w ) = ( N ` w ) ) <-> ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) ) |
| 24 | 23 | imbi2d | |- ( w = y -> ( ( ph -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) <-> ( ph -> ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) ) ) |
| 25 | r19.21v | |- ( A. y e. w ( ph -> ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) <-> ( ph -> A. y e. w ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) ) |
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| 26 | 16 | a1i | |- ( ph -> Ord dom M ) |
| 27 | ordelss | |- ( ( Ord dom M /\ w e. dom M ) -> w C_ dom M ) |
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| 28 | 26 27 | sylan | |- ( ( ph /\ w e. dom M ) -> w C_ dom M ) |
| 29 | 28 | sselda | |- ( ( ( ph /\ w e. dom M ) /\ y e. w ) -> y e. dom M ) |
| 30 | pm2.27 | |- ( y e. dom M -> ( ( y e. dom M -> ( M ` y ) = ( N ` y ) ) -> ( M ` y ) = ( N ` y ) ) ) |
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| 31 | 29 30 | syl | |- ( ( ( ph /\ w e. dom M ) /\ y e. w ) -> ( ( y e. dom M -> ( M ` y ) = ( N ` y ) ) -> ( M ` y ) = ( N ` y ) ) ) |
| 32 | 31 | ralimdva | |- ( ( ph /\ w e. dom M ) -> ( A. y e. w ( y e. dom M -> ( M ` y ) = ( N ` y ) ) -> A. y e. w ( M ` y ) = ( N ` y ) ) ) |
| 33 | fnssres | |- ( ( M Fn dom M /\ w C_ dom M ) -> ( M |` w ) Fn w ) |
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| 34 | 11 28 33 | syl2an2r | |- ( ( ph /\ w e. dom M ) -> ( M |` w ) Fn w ) |
| 35 | 8 | adantr | |- ( ( ph /\ w e. dom M ) -> dom M C_ dom N ) |
| 36 | 28 35 | sstrd | |- ( ( ph /\ w e. dom M ) -> w C_ dom N ) |
| 37 | fnssres | |- ( ( N Fn dom N /\ w C_ dom N ) -> ( N |` w ) Fn w ) |
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| 38 | 14 36 37 | syl2an2r | |- ( ( ph /\ w e. dom M ) -> ( N |` w ) Fn w ) |
| 39 | eqfnfv | |- ( ( ( M |` w ) Fn w /\ ( N |` w ) Fn w ) -> ( ( M |` w ) = ( N |` w ) <-> A. y e. w ( ( M |` w ) ` y ) = ( ( N |` w ) ` y ) ) ) |
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| 40 | 34 38 39 | syl2anc | |- ( ( ph /\ w e. dom M ) -> ( ( M |` w ) = ( N |` w ) <-> A. y e. w ( ( M |` w ) ` y ) = ( ( N |` w ) ` y ) ) ) |
| 41 | fvres | |- ( y e. w -> ( ( M |` w ) ` y ) = ( M ` y ) ) |
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| 42 | fvres | |- ( y e. w -> ( ( N |` w ) ` y ) = ( N ` y ) ) |
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| 43 | 41 42 | eqeq12d | |- ( y e. w -> ( ( ( M |` w ) ` y ) = ( ( N |` w ) ` y ) <-> ( M ` y ) = ( N ` y ) ) ) |
| 44 | 43 | ralbiia | |- ( A. y e. w ( ( M |` w ) ` y ) = ( ( N |` w ) ` y ) <-> A. y e. w ( M ` y ) = ( N ` y ) ) |
| 45 | 40 44 | bitrdi | |- ( ( ph /\ w e. dom M ) -> ( ( M |` w ) = ( N |` w ) <-> A. y e. w ( M ` y ) = ( N ` y ) ) ) |
| 46 | 2 | ad2antrr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> A e. V ) |
| 47 | simpll | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ph ) |
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| 48 | 47 3 | sylan | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ ( x C_ A /\ r C_ ( x X. x ) /\ r We x ) ) -> ( x F r ) e. A ) |
| 49 | 4 | ad2antrr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> X W R ) |
| 50 | 5 | ad2antrr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> Y W S ) |
| 51 | simplr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> w e. dom M ) |
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| 52 | 8 | sselda | |- ( ( ph /\ w e. dom M ) -> w e. dom N ) |
| 53 | 52 | adantr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> w e. dom N ) |
| 54 | simpr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( M |` w ) = ( N |` w ) ) |
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| 55 | 1 46 48 49 50 6 7 51 53 54 | fpwwe2lem6 | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ y R ( M ` w ) ) -> ( y S ( N ` w ) /\ ( z R ( M ` w ) -> ( y R z <-> y S z ) ) ) ) |
| 56 | 55 | simpld | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ y R ( M ` w ) ) -> y S ( N ` w ) ) |
| 57 | 54 | eqcomd | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( N |` w ) = ( M |` w ) ) |
| 58 | 1 46 48 50 49 7 6 53 51 57 | fpwwe2lem6 | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ y S ( N ` w ) ) -> ( y R ( M ` w ) /\ ( z S ( N ` w ) -> ( y S z <-> y R z ) ) ) ) |
| 59 | 58 | simpld | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ y S ( N ` w ) ) -> y R ( M ` w ) ) |
| 60 | 56 59 | impbida | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( y R ( M ` w ) <-> y S ( N ` w ) ) ) |
| 61 | fvex | |- ( M ` w ) e. _V |
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| 62 | vex | |- y e. _V |
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| 63 | 62 | eliniseg | |- ( ( M ` w ) e. _V -> ( y e. ( `' R " { ( M ` w ) } ) <-> y R ( M ` w ) ) ) |
| 64 | 61 63 | ax-mp | |- ( y e. ( `' R " { ( M ` w ) } ) <-> y R ( M ` w ) ) |
| 65 | fvex | |- ( N ` w ) e. _V |
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| 66 | 62 | eliniseg | |- ( ( N ` w ) e. _V -> ( y e. ( `' S " { ( N ` w ) } ) <-> y S ( N ` w ) ) ) |
| 67 | 65 66 | ax-mp | |- ( y e. ( `' S " { ( N ` w ) } ) <-> y S ( N ` w ) ) |
| 68 | 60 64 67 | 3bitr4g | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( y e. ( `' R " { ( M ` w ) } ) <-> y e. ( `' S " { ( N ` w ) } ) ) ) |
| 69 | 68 | eqrdv | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( `' R " { ( M ` w ) } ) = ( `' S " { ( N ` w ) } ) ) |
| 70 | relinxp | |- Rel ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) |
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| 71 | relinxp | |- Rel ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) |
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| 72 | vex | |- z e. _V |
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| 73 | 72 | eliniseg | |- ( ( M ` w ) e. _V -> ( z e. ( `' R " { ( M ` w ) } ) <-> z R ( M ` w ) ) ) |
| 74 | 63 73 | anbi12d | |- ( ( M ` w ) e. _V -> ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) <-> ( y R ( M ` w ) /\ z R ( M ` w ) ) ) ) |
| 75 | 61 74 | ax-mp | |- ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) <-> ( y R ( M ` w ) /\ z R ( M ` w ) ) ) |
| 76 | 55 | simprd | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ y R ( M ` w ) ) -> ( z R ( M ` w ) -> ( y R z <-> y S z ) ) ) |
| 77 | 76 | impr | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ ( y R ( M ` w ) /\ z R ( M ` w ) ) ) -> ( y R z <-> y S z ) ) |
| 78 | 75 77 | sylan2b | |- ( ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) /\ ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) ) -> ( y R z <-> y S z ) ) |
| 79 | 78 | pm5.32da | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) /\ y R z ) <-> ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) /\ y S z ) ) ) |
| 80 | df-br | |- ( y ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) z <-> <. y , z >. e. ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) |
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| 81 | brinxp2 | |- ( y ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) z <-> ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) /\ y R z ) ) |
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| 82 | 80 81 | bitr3i | |- ( <. y , z >. e. ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) <-> ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) /\ y R z ) ) |
| 83 | df-br | |- ( y ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) z <-> <. y , z >. e. ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) |
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| 84 | brinxp2 | |- ( y ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) z <-> ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) /\ y S z ) ) |
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| 85 | 83 84 | bitr3i | |- ( <. y , z >. e. ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) <-> ( ( y e. ( `' R " { ( M ` w ) } ) /\ z e. ( `' R " { ( M ` w ) } ) ) /\ y S z ) ) |
| 86 | 79 82 85 | 3bitr4g | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( <. y , z >. e. ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) <-> <. y , z >. e. ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) ) |
| 87 | 70 71 86 | eqrelrdv | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) = ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) |
| 88 | 69 | sqxpeqd | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) = ( ( `' S " { ( N ` w ) } ) X. ( `' S " { ( N ` w ) } ) ) ) |
| 89 | 88 | ineq2d | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( S i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) = ( S i^i ( ( `' S " { ( N ` w ) } ) X. ( `' S " { ( N ` w ) } ) ) ) ) |
| 90 | 87 89 | eqtrd | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) = ( S i^i ( ( `' S " { ( N ` w ) } ) X. ( `' S " { ( N ` w ) } ) ) ) ) |
| 91 | 69 90 | oveq12d | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( ( `' R " { ( M ` w ) } ) F ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) = ( ( `' S " { ( N ` w ) } ) F ( S i^i ( ( `' S " { ( N ` w ) } ) X. ( `' S " { ( N ` w ) } ) ) ) ) ) |
| 92 | 9 | ffvelcdmi | |- ( w e. dom M -> ( M ` w ) e. X ) |
| 93 | 92 | adantl | |- ( ( ph /\ w e. dom M ) -> ( M ` w ) e. X ) |
| 94 | 93 | adantr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( M ` w ) e. X ) |
| 95 | 1 2 4 | fpwwe2lem3 | |- ( ( ph /\ ( M ` w ) e. X ) -> ( ( `' R " { ( M ` w ) } ) F ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) = ( M ` w ) ) |
| 96 | 47 94 95 | syl2anc | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( ( `' R " { ( M ` w ) } ) F ( R i^i ( ( `' R " { ( M ` w ) } ) X. ( `' R " { ( M ` w ) } ) ) ) ) = ( M ` w ) ) |
| 97 | 12 | ffvelcdmi | |- ( w e. dom N -> ( N ` w ) e. Y ) |
| 98 | 52 97 | syl | |- ( ( ph /\ w e. dom M ) -> ( N ` w ) e. Y ) |
| 99 | 98 | adantr | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( N ` w ) e. Y ) |
| 100 | 1 2 5 | fpwwe2lem3 | |- ( ( ph /\ ( N ` w ) e. Y ) -> ( ( `' S " { ( N ` w ) } ) F ( S i^i ( ( `' S " { ( N ` w ) } ) X. ( `' S " { ( N ` w ) } ) ) ) ) = ( N ` w ) ) |
| 101 | 47 99 100 | syl2anc | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( ( `' S " { ( N ` w ) } ) F ( S i^i ( ( `' S " { ( N ` w ) } ) X. ( `' S " { ( N ` w ) } ) ) ) ) = ( N ` w ) ) |
| 102 | 91 96 101 | 3eqtr3d | |- ( ( ( ph /\ w e. dom M ) /\ ( M |` w ) = ( N |` w ) ) -> ( M ` w ) = ( N ` w ) ) |
| 103 | 102 | ex | |- ( ( ph /\ w e. dom M ) -> ( ( M |` w ) = ( N |` w ) -> ( M ` w ) = ( N ` w ) ) ) |
| 104 | 45 103 | sylbird | |- ( ( ph /\ w e. dom M ) -> ( A. y e. w ( M ` y ) = ( N ` y ) -> ( M ` w ) = ( N ` w ) ) ) |
| 105 | 32 104 | syld | |- ( ( ph /\ w e. dom M ) -> ( A. y e. w ( y e. dom M -> ( M ` y ) = ( N ` y ) ) -> ( M ` w ) = ( N ` w ) ) ) |
| 106 | 105 | ex | |- ( ph -> ( w e. dom M -> ( A. y e. w ( y e. dom M -> ( M ` y ) = ( N ` y ) ) -> ( M ` w ) = ( N ` w ) ) ) ) |
| 107 | 106 | com23 | |- ( ph -> ( A. y e. w ( y e. dom M -> ( M ` y ) = ( N ` y ) ) -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) ) |
| 108 | 107 | a2i | |- ( ( ph -> A. y e. w ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) -> ( ph -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) ) |
| 109 | 25 108 | sylbi | |- ( A. y e. w ( ph -> ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) -> ( ph -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) ) |
| 110 | 109 | a1i | |- ( w e. On -> ( A. y e. w ( ph -> ( y e. dom M -> ( M ` y ) = ( N ` y ) ) ) -> ( ph -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) ) ) |
| 111 | 24 110 | tfis2 | |- ( w e. On -> ( ph -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) ) |
| 112 | 111 | com3l | |- ( ph -> ( w e. dom M -> ( w e. On -> ( M ` w ) = ( N ` w ) ) ) ) |
| 113 | 18 112 | mpdi | |- ( ph -> ( w e. dom M -> ( M ` w ) = ( N ` w ) ) ) |
| 114 | 113 | imp | |- ( ( ph /\ w e. dom M ) -> ( M ` w ) = ( N ` w ) ) |
| 115 | fvres | |- ( w e. dom M -> ( ( N |` dom M ) ` w ) = ( N ` w ) ) |
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| 116 | 115 | adantl | |- ( ( ph /\ w e. dom M ) -> ( ( N |` dom M ) ` w ) = ( N ` w ) ) |
| 117 | 114 116 | eqtr4d | |- ( ( ph /\ w e. dom M ) -> ( M ` w ) = ( ( N |` dom M ) ` w ) ) |
| 118 | 11 15 117 | eqfnfvd | |- ( ph -> M = ( N |` dom M ) ) |