Metamath Proof Explorer


Theorem wlimeq12

Description: Equality theorem for the limit class. (Contributed by Scott Fenton, 15-Jun-2018) (Proof shortened by AV, 10-Oct-2021)

Ref Expression
Assertion wlimeq12 ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → WLim ( 𝑅 , 𝐴 ) = WLim ( 𝑆 , 𝐵 ) )

Proof

Step Hyp Ref Expression
1 simpr ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → 𝐴 = 𝐵 )
2 simpl ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → 𝑅 = 𝑆 )
3 1 1 2 infeq123d ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → inf ( 𝐴 , 𝐴 , 𝑅 ) = inf ( 𝐵 , 𝐵 , 𝑆 ) )
4 3 neeq2d ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → ( 𝑥 ≠ inf ( 𝐴 , 𝐴 , 𝑅 ) ↔ 𝑥 ≠ inf ( 𝐵 , 𝐵 , 𝑆 ) ) )
5 equid 𝑥 = 𝑥
6 predeq123 ( ( 𝑅 = 𝑆𝐴 = 𝐵𝑥 = 𝑥 ) → Pred ( 𝑅 , 𝐴 , 𝑥 ) = Pred ( 𝑆 , 𝐵 , 𝑥 ) )
7 5 6 mp3an3 ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → Pred ( 𝑅 , 𝐴 , 𝑥 ) = Pred ( 𝑆 , 𝐵 , 𝑥 ) )
8 7 1 2 supeq123d ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → sup ( Pred ( 𝑅 , 𝐴 , 𝑥 ) , 𝐴 , 𝑅 ) = sup ( Pred ( 𝑆 , 𝐵 , 𝑥 ) , 𝐵 , 𝑆 ) )
9 8 eqeq2d ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → ( 𝑥 = sup ( Pred ( 𝑅 , 𝐴 , 𝑥 ) , 𝐴 , 𝑅 ) ↔ 𝑥 = sup ( Pred ( 𝑆 , 𝐵 , 𝑥 ) , 𝐵 , 𝑆 ) ) )
10 4 9 anbi12d ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → ( ( 𝑥 ≠ inf ( 𝐴 , 𝐴 , 𝑅 ) ∧ 𝑥 = sup ( Pred ( 𝑅 , 𝐴 , 𝑥 ) , 𝐴 , 𝑅 ) ) ↔ ( 𝑥 ≠ inf ( 𝐵 , 𝐵 , 𝑆 ) ∧ 𝑥 = sup ( Pred ( 𝑆 , 𝐵 , 𝑥 ) , 𝐵 , 𝑆 ) ) ) )
11 1 10 rabeqbidv ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → { 𝑥𝐴 ∣ ( 𝑥 ≠ inf ( 𝐴 , 𝐴 , 𝑅 ) ∧ 𝑥 = sup ( Pred ( 𝑅 , 𝐴 , 𝑥 ) , 𝐴 , 𝑅 ) ) } = { 𝑥𝐵 ∣ ( 𝑥 ≠ inf ( 𝐵 , 𝐵 , 𝑆 ) ∧ 𝑥 = sup ( Pred ( 𝑆 , 𝐵 , 𝑥 ) , 𝐵 , 𝑆 ) ) } )
12 df-wlim WLim ( 𝑅 , 𝐴 ) = { 𝑥𝐴 ∣ ( 𝑥 ≠ inf ( 𝐴 , 𝐴 , 𝑅 ) ∧ 𝑥 = sup ( Pred ( 𝑅 , 𝐴 , 𝑥 ) , 𝐴 , 𝑅 ) ) }
13 df-wlim WLim ( 𝑆 , 𝐵 ) = { 𝑥𝐵 ∣ ( 𝑥 ≠ inf ( 𝐵 , 𝐵 , 𝑆 ) ∧ 𝑥 = sup ( Pred ( 𝑆 , 𝐵 , 𝑥 ) , 𝐵 , 𝑆 ) ) }
14 11 12 13 3eqtr4g ( ( 𝑅 = 𝑆𝐴 = 𝐵 ) → WLim ( 𝑅 , 𝐴 ) = WLim ( 𝑆 , 𝐵 ) )