Metamath Proof Explorer


Theorem nodenselem5

Description: Lemma for nodense . If the birthdays of two distinct surreals are equal, then the ordinal from nodenselem4 is an element of that birthday. (Contributed by Scott Fenton, 16-Jun-2011)

Ref Expression
Assertion nodenselem5 ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → { 𝑎 ∈ On ∣ ( 𝐴𝑎 ) ≠ ( 𝐵𝑎 ) } ∈ ( bday 𝐴 ) )

Proof

Step Hyp Ref Expression
1 simpll ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → 𝐴 No )
2 simplr ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → 𝐵 No )
3 sltso <s Or No
4 sonr ( ( <s Or No 𝐴 No ) → ¬ 𝐴 <s 𝐴 )
5 3 4 mpan ( 𝐴 No → ¬ 𝐴 <s 𝐴 )
6 breq2 ( 𝐴 = 𝐵 → ( 𝐴 <s 𝐴𝐴 <s 𝐵 ) )
7 6 notbid ( 𝐴 = 𝐵 → ( ¬ 𝐴 <s 𝐴 ↔ ¬ 𝐴 <s 𝐵 ) )
8 5 7 syl5ibcom ( 𝐴 No → ( 𝐴 = 𝐵 → ¬ 𝐴 <s 𝐵 ) )
9 8 necon2ad ( 𝐴 No → ( 𝐴 <s 𝐵𝐴𝐵 ) )
10 9 adantr ( ( 𝐴 No 𝐵 No ) → ( 𝐴 <s 𝐵𝐴𝐵 ) )
11 10 imp ( ( ( 𝐴 No 𝐵 No ) ∧ 𝐴 <s 𝐵 ) → 𝐴𝐵 )
12 11 adantrl ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → 𝐴𝐵 )
13 nosepdm ( ( 𝐴 No 𝐵 No 𝐴𝐵 ) → { 𝑎 ∈ On ∣ ( 𝐴𝑎 ) ≠ ( 𝐵𝑎 ) } ∈ ( dom 𝐴 ∪ dom 𝐵 ) )
14 1 2 12 13 syl3anc ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → { 𝑎 ∈ On ∣ ( 𝐴𝑎 ) ≠ ( 𝐵𝑎 ) } ∈ ( dom 𝐴 ∪ dom 𝐵 ) )
15 unidm ( ( bday 𝐴 ) ∪ ( bday 𝐴 ) ) = ( bday 𝐴 )
16 simprl ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( bday 𝐴 ) = ( bday 𝐵 ) )
17 16 uneq2d ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( ( bday 𝐴 ) ∪ ( bday 𝐴 ) ) = ( ( bday 𝐴 ) ∪ ( bday 𝐵 ) ) )
18 15 17 syl5reqr ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( ( bday 𝐴 ) ∪ ( bday 𝐵 ) ) = ( bday 𝐴 ) )
19 bdayval ( 𝐴 No → ( bday 𝐴 ) = dom 𝐴 )
20 1 19 syl ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( bday 𝐴 ) = dom 𝐴 )
21 bdayval ( 𝐵 No → ( bday 𝐵 ) = dom 𝐵 )
22 2 21 syl ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( bday 𝐵 ) = dom 𝐵 )
23 20 22 uneq12d ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( ( bday 𝐴 ) ∪ ( bday 𝐵 ) ) = ( dom 𝐴 ∪ dom 𝐵 ) )
24 18 23 20 3eqtr3d ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → ( dom 𝐴 ∪ dom 𝐵 ) = dom 𝐴 )
25 14 24 eleqtrd ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → { 𝑎 ∈ On ∣ ( 𝐴𝑎 ) ≠ ( 𝐵𝑎 ) } ∈ dom 𝐴 )
26 25 20 eleqtrrd ( ( ( 𝐴 No 𝐵 No ) ∧ ( ( bday 𝐴 ) = ( bday 𝐵 ) ∧ 𝐴 <s 𝐵 ) ) → { 𝑎 ∈ On ∣ ( 𝐴𝑎 ) ≠ ( 𝐵𝑎 ) } ∈ ( bday 𝐴 ) )