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Description: If the property A is preserved under topological products, then so is the property of being locally A . (Contributed by Mario Carneiro, 10-Mar-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | txlly.1 | |- ( ( j e. A /\ k e. A ) -> ( j tX k ) e. A ) |
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| Assertion | txlly | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( R tX S ) e. Locally A ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | txlly.1 | |- ( ( j e. A /\ k e. A ) -> ( j tX k ) e. A ) |
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| 2 | llytop | |- ( R e. Locally A -> R e. Top ) |
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| 3 | llytop | |- ( S e. Locally A -> S e. Top ) |
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| 4 | txtop | |- ( ( R e. Top /\ S e. Top ) -> ( R tX S ) e. Top ) |
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| 5 | 2 3 4 | syl2an | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( R tX S ) e. Top ) |
| 6 | eltx | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( x e. ( R tX S ) <-> A. y e. x E. u e. R E. v e. S ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) |
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| 7 | simpll | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> R e. Locally A ) |
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| 8 | simprll | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> u e. R ) |
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| 9 | simprrl | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> y e. ( u X. v ) ) |
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| 10 | xp1st | |- ( y e. ( u X. v ) -> ( 1st ` y ) e. u ) |
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| 11 | 9 10 | syl | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> ( 1st ` y ) e. u ) |
| 12 | llyi | |- ( ( R e. Locally A /\ u e. R /\ ( 1st ` y ) e. u ) -> E. r e. R ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) ) |
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| 13 | 7 8 11 12 | syl3anc | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> E. r e. R ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) ) |
| 14 | simplr | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> S e. Locally A ) |
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| 15 | simprlr | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> v e. S ) |
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| 16 | xp2nd | |- ( y e. ( u X. v ) -> ( 2nd ` y ) e. v ) |
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| 17 | 9 16 | syl | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> ( 2nd ` y ) e. v ) |
| 18 | llyi | |- ( ( S e. Locally A /\ v e. S /\ ( 2nd ` y ) e. v ) -> E. s e. S ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) |
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| 19 | 14 15 17 18 | syl3anc | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> E. s e. S ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) |
| 20 | reeanv | |- ( E. r e. R E. s e. S ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) <-> ( E. r e. R ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ E. s e. S ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) |
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| 21 | 2 | ad3antrrr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> R e. Top ) |
| 22 | 3 | ad3antlr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> S e. Top ) |
| 23 | simprll | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> r e. R ) |
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| 24 | simprlr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> s e. S ) |
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| 25 | txopn | |- ( ( ( R e. Top /\ S e. Top ) /\ ( r e. R /\ s e. S ) ) -> ( r X. s ) e. ( R tX S ) ) |
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| 26 | 21 22 23 24 25 | syl22anc | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( r X. s ) e. ( R tX S ) ) |
| 27 | simprl1 | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> r C_ u ) |
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| 28 | simprr1 | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> s C_ v ) |
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| 29 | xpss12 | |- ( ( r C_ u /\ s C_ v ) -> ( r X. s ) C_ ( u X. v ) ) |
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| 30 | 27 28 29 | syl2anc | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> ( r X. s ) C_ ( u X. v ) ) |
| 31 | simprrr | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> ( u X. v ) C_ x ) |
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| 32 | 30 31 | sylan9ssr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( r X. s ) C_ x ) |
| 33 | vex | |- x e. _V |
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| 34 | 33 | elpw2 | |- ( ( r X. s ) e. ~P x <-> ( r X. s ) C_ x ) |
| 35 | 32 34 | sylibr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( r X. s ) e. ~P x ) |
| 36 | 26 35 | elind | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( r X. s ) e. ( ( R tX S ) i^i ~P x ) ) |
| 37 | 1st2nd2 | |- ( y e. ( u X. v ) -> y = <. ( 1st ` y ) , ( 2nd ` y ) >. ) |
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| 38 | 9 37 | syl | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> y = <. ( 1st ` y ) , ( 2nd ` y ) >. ) |
| 39 | 38 | adantr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> y = <. ( 1st ` y ) , ( 2nd ` y ) >. ) |
| 40 | simprl2 | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> ( 1st ` y ) e. r ) |
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| 41 | simprr2 | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> ( 2nd ` y ) e. s ) |
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| 42 | 40 41 | opelxpd | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> <. ( 1st ` y ) , ( 2nd ` y ) >. e. ( r X. s ) ) |
| 43 | 42 | adantl | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> <. ( 1st ` y ) , ( 2nd ` y ) >. e. ( r X. s ) ) |
| 44 | 39 43 | eqeltrd | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> y e. ( r X. s ) ) |
| 45 | txrest | |- ( ( ( R e. Top /\ S e. Top ) /\ ( r e. R /\ s e. S ) ) -> ( ( R tX S ) |`t ( r X. s ) ) = ( ( R |`t r ) tX ( S |`t s ) ) ) |
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| 46 | 21 22 23 24 45 | syl22anc | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( ( R tX S ) |`t ( r X. s ) ) = ( ( R |`t r ) tX ( S |`t s ) ) ) |
| 47 | simprl3 | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> ( R |`t r ) e. A ) |
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| 48 | simprr3 | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> ( S |`t s ) e. A ) |
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| 49 | 1 | caovcl | |- ( ( ( R |`t r ) e. A /\ ( S |`t s ) e. A ) -> ( ( R |`t r ) tX ( S |`t s ) ) e. A ) |
| 50 | 47 48 49 | syl2anc | |- ( ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) -> ( ( R |`t r ) tX ( S |`t s ) ) e. A ) |
| 51 | 50 | adantl | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( ( R |`t r ) tX ( S |`t s ) ) e. A ) |
| 52 | 46 51 | eqeltrd | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> ( ( R tX S ) |`t ( r X. s ) ) e. A ) |
| 53 | eleq2 | |- ( z = ( r X. s ) -> ( y e. z <-> y e. ( r X. s ) ) ) |
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| 54 | oveq2 | |- ( z = ( r X. s ) -> ( ( R tX S ) |`t z ) = ( ( R tX S ) |`t ( r X. s ) ) ) |
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| 55 | 54 | eleq1d | |- ( z = ( r X. s ) -> ( ( ( R tX S ) |`t z ) e. A <-> ( ( R tX S ) |`t ( r X. s ) ) e. A ) ) |
| 56 | 53 55 | anbi12d | |- ( z = ( r X. s ) -> ( ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) <-> ( y e. ( r X. s ) /\ ( ( R tX S ) |`t ( r X. s ) ) e. A ) ) ) |
| 57 | 56 | rspcev | |- ( ( ( r X. s ) e. ( ( R tX S ) i^i ~P x ) /\ ( y e. ( r X. s ) /\ ( ( R tX S ) |`t ( r X. s ) ) e. A ) ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) |
| 58 | 36 44 52 57 | syl12anc | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( ( r e. R /\ s e. S ) /\ ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) ) ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) |
| 59 | 58 | expr | |- ( ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) /\ ( r e. R /\ s e. S ) ) -> ( ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 60 | 59 | rexlimdvva | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> ( E. r e. R E. s e. S ( ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 61 | 20 60 | biimtrrid | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> ( ( E. r e. R ( r C_ u /\ ( 1st ` y ) e. r /\ ( R |`t r ) e. A ) /\ E. s e. S ( s C_ v /\ ( 2nd ` y ) e. s /\ ( S |`t s ) e. A ) ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 62 | 13 19 61 | mp2and | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( ( u e. R /\ v e. S ) /\ ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) ) ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) |
| 63 | 62 | expr | |- ( ( ( R e. Locally A /\ S e. Locally A ) /\ ( u e. R /\ v e. S ) ) -> ( ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 64 | 63 | rexlimdvva | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( E. u e. R E. v e. S ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) -> E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 65 | 64 | ralimdv | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( A. y e. x E. u e. R E. v e. S ( y e. ( u X. v ) /\ ( u X. v ) C_ x ) -> A. y e. x E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 66 | 6 65 | sylbid | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( x e. ( R tX S ) -> A. y e. x E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
| 67 | 66 | ralrimiv | |- ( ( R e. Locally A /\ S e. Locally A ) -> A. x e. ( R tX S ) A. y e. x E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) |
| 68 | islly | |- ( ( R tX S ) e. Locally A <-> ( ( R tX S ) e. Top /\ A. x e. ( R tX S ) A. y e. x E. z e. ( ( R tX S ) i^i ~P x ) ( y e. z /\ ( ( R tX S ) |`t z ) e. A ) ) ) |
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| 69 | 5 67 68 | sylanbrc | |- ( ( R e. Locally A /\ S e. Locally A ) -> ( R tX S ) e. Locally A ) |