Metamath Proof Explorer


Theorem kmlem9

Description: Lemma for 5-quantifier AC of Kurt Maes, Th. 4, part of 3 => 4. (Contributed by NM, 25-Mar-2004)

Ref Expression
Hypothesis kmlem9.1 𝐴 = { 𝑢 ∣ ∃ 𝑡𝑥 𝑢 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) }
Assertion kmlem9 𝑧𝐴𝑤𝐴 ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ )

Proof

Step Hyp Ref Expression
1 kmlem9.1 𝐴 = { 𝑢 ∣ ∃ 𝑡𝑥 𝑢 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) }
2 vex 𝑧 ∈ V
3 eqeq1 ( 𝑢 = 𝑧 → ( 𝑢 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ↔ 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ) )
4 3 rexbidv ( 𝑢 = 𝑧 → ( ∃ 𝑡𝑥 𝑢 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ↔ ∃ 𝑡𝑥 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ) )
5 2 4 1 elab2 ( 𝑧𝐴 ↔ ∃ 𝑡𝑥 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) )
6 vex 𝑤 ∈ V
7 eqeq1 ( 𝑢 = 𝑤 → ( 𝑢 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ↔ 𝑤 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ) )
8 7 rexbidv ( 𝑢 = 𝑤 → ( ∃ 𝑡𝑥 𝑢 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ↔ ∃ 𝑡𝑥 𝑤 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ) )
9 6 8 1 elab2 ( 𝑤𝐴 ↔ ∃ 𝑡𝑥 𝑤 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) )
10 difeq1 ( 𝑡 = → ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) = ( ( 𝑥 ∖ { 𝑡 } ) ) )
11 sneq ( 𝑡 = → { 𝑡 } = { } )
12 11 difeq2d ( 𝑡 = → ( 𝑥 ∖ { 𝑡 } ) = ( 𝑥 ∖ { } ) )
13 12 unieqd ( 𝑡 = ( 𝑥 ∖ { 𝑡 } ) = ( 𝑥 ∖ { } ) )
14 13 difeq2d ( 𝑡 = → ( ( 𝑥 ∖ { 𝑡 } ) ) = ( ( 𝑥 ∖ { } ) ) )
15 10 14 eqtrd ( 𝑡 = → ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) = ( ( 𝑥 ∖ { } ) ) )
16 15 eqeq2d ( 𝑡 = → ( 𝑤 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ↔ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) )
17 16 cbvrexvw ( ∃ 𝑡𝑥 𝑤 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ↔ ∃ 𝑥 𝑤 = ( ( 𝑥 ∖ { } ) ) )
18 9 17 bitri ( 𝑤𝐴 ↔ ∃ 𝑥 𝑤 = ( ( 𝑥 ∖ { } ) ) )
19 reeanv ( ∃ 𝑡𝑥𝑥 ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) ↔ ( ∃ 𝑡𝑥 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ ∃ 𝑥 𝑤 = ( ( 𝑥 ∖ { } ) ) ) )
20 eqeq12 ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧 = 𝑤 ↔ ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) = ( ( 𝑥 ∖ { } ) ) ) )
21 15 20 syl5ibr ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑡 = 𝑧 = 𝑤 ) )
22 21 necon3d ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧𝑤𝑡 ) )
23 kmlem5 ( ( 𝑥𝑡 ) → ( ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∩ ( ( 𝑥 ∖ { } ) ) ) = ∅ )
24 ineq12 ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧𝑤 ) = ( ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∩ ( ( 𝑥 ∖ { } ) ) ) )
25 24 eqeq1d ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( ( 𝑧𝑤 ) = ∅ ↔ ( ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∩ ( ( 𝑥 ∖ { } ) ) ) = ∅ ) )
26 23 25 syl5ibr ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( ( 𝑥𝑡 ) → ( 𝑧𝑤 ) = ∅ ) )
27 26 expd ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑥 → ( 𝑡 → ( 𝑧𝑤 ) = ∅ ) ) )
28 22 27 syl5d ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑥 → ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ ) ) )
29 28 com12 ( 𝑥 → ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ ) ) )
30 29 adantl ( ( 𝑡𝑥𝑥 ) → ( ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ ) ) )
31 30 rexlimivv ( ∃ 𝑡𝑥𝑥 ( 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ ) )
32 19 31 sylbir ( ( ∃ 𝑡𝑥 𝑧 = ( 𝑡 ( 𝑥 ∖ { 𝑡 } ) ) ∧ ∃ 𝑥 𝑤 = ( ( 𝑥 ∖ { } ) ) ) → ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ ) )
33 5 18 32 syl2anb ( ( 𝑧𝐴𝑤𝐴 ) → ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ ) )
34 33 rgen2 𝑧𝐴𝑤𝐴 ( 𝑧𝑤 → ( 𝑧𝑤 ) = ∅ )