Metamath Proof Explorer


Theorem prneimg

Description: Two pairs are not equal if at least one element of the first pair is not contained in the second pair. (Contributed by Alexander van der Vekens, 13-Aug-2017)

Ref Expression
Assertion prneimg ( ( ( 𝐴𝑈𝐵𝑉 ) ∧ ( 𝐶𝑋𝐷𝑌 ) ) → ( ( ( 𝐴𝐶𝐴𝐷 ) ∨ ( 𝐵𝐶𝐵𝐷 ) ) → { 𝐴 , 𝐵 } ≠ { 𝐶 , 𝐷 } ) )

Proof

Step Hyp Ref Expression
1 preq12bg ( ( ( 𝐴𝑈𝐵𝑉 ) ∧ ( 𝐶𝑋𝐷𝑌 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( ( 𝐴 = 𝐶𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷𝐵 = 𝐶 ) ) ) )
2 orddi ( ( ( 𝐴 = 𝐶𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷𝐵 = 𝐶 ) ) ↔ ( ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐴 = 𝐶𝐵 = 𝐶 ) ) ∧ ( ( 𝐵 = 𝐷𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐷𝐵 = 𝐶 ) ) ) )
3 simpll ( ( ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐴 = 𝐶𝐵 = 𝐶 ) ) ∧ ( ( 𝐵 = 𝐷𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐷𝐵 = 𝐶 ) ) ) → ( 𝐴 = 𝐶𝐴 = 𝐷 ) )
4 pm1.4 ( ( 𝐵 = 𝐷𝐵 = 𝐶 ) → ( 𝐵 = 𝐶𝐵 = 𝐷 ) )
5 4 ad2antll ( ( ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐴 = 𝐶𝐵 = 𝐶 ) ) ∧ ( ( 𝐵 = 𝐷𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐷𝐵 = 𝐶 ) ) ) → ( 𝐵 = 𝐶𝐵 = 𝐷 ) )
6 3 5 jca ( ( ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐴 = 𝐶𝐵 = 𝐶 ) ) ∧ ( ( 𝐵 = 𝐷𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐷𝐵 = 𝐶 ) ) ) → ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐶𝐵 = 𝐷 ) ) )
7 2 6 sylbi ( ( ( 𝐴 = 𝐶𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷𝐵 = 𝐶 ) ) → ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐶𝐵 = 𝐷 ) ) )
8 1 7 syl6bi ( ( ( 𝐴𝑈𝐵𝑉 ) ∧ ( 𝐶𝑋𝐷𝑌 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐶𝐵 = 𝐷 ) ) ) )
9 ianor ( ¬ ( 𝐴𝐶𝐴𝐷 ) ↔ ( ¬ 𝐴𝐶 ∨ ¬ 𝐴𝐷 ) )
10 nne ( ¬ 𝐴𝐶𝐴 = 𝐶 )
11 nne ( ¬ 𝐴𝐷𝐴 = 𝐷 )
12 10 11 orbi12i ( ( ¬ 𝐴𝐶 ∨ ¬ 𝐴𝐷 ) ↔ ( 𝐴 = 𝐶𝐴 = 𝐷 ) )
13 9 12 bitr2i ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ↔ ¬ ( 𝐴𝐶𝐴𝐷 ) )
14 ianor ( ¬ ( 𝐵𝐶𝐵𝐷 ) ↔ ( ¬ 𝐵𝐶 ∨ ¬ 𝐵𝐷 ) )
15 nne ( ¬ 𝐵𝐶𝐵 = 𝐶 )
16 nne ( ¬ 𝐵𝐷𝐵 = 𝐷 )
17 15 16 orbi12i ( ( ¬ 𝐵𝐶 ∨ ¬ 𝐵𝐷 ) ↔ ( 𝐵 = 𝐶𝐵 = 𝐷 ) )
18 14 17 bitr2i ( ( 𝐵 = 𝐶𝐵 = 𝐷 ) ↔ ¬ ( 𝐵𝐶𝐵𝐷 ) )
19 13 18 anbi12i ( ( ( 𝐴 = 𝐶𝐴 = 𝐷 ) ∧ ( 𝐵 = 𝐶𝐵 = 𝐷 ) ) ↔ ( ¬ ( 𝐴𝐶𝐴𝐷 ) ∧ ¬ ( 𝐵𝐶𝐵𝐷 ) ) )
20 8 19 syl6ib ( ( ( 𝐴𝑈𝐵𝑉 ) ∧ ( 𝐶𝑋𝐷𝑌 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( ¬ ( 𝐴𝐶𝐴𝐷 ) ∧ ¬ ( 𝐵𝐶𝐵𝐷 ) ) ) )
21 pm4.56 ( ( ¬ ( 𝐴𝐶𝐴𝐷 ) ∧ ¬ ( 𝐵𝐶𝐵𝐷 ) ) ↔ ¬ ( ( 𝐴𝐶𝐴𝐷 ) ∨ ( 𝐵𝐶𝐵𝐷 ) ) )
22 20 21 syl6ib ( ( ( 𝐴𝑈𝐵𝑉 ) ∧ ( 𝐶𝑋𝐷𝑌 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ¬ ( ( 𝐴𝐶𝐴𝐷 ) ∨ ( 𝐵𝐶𝐵𝐷 ) ) ) )
23 22 necon2ad ( ( ( 𝐴𝑈𝐵𝑉 ) ∧ ( 𝐶𝑋𝐷𝑌 ) ) → ( ( ( 𝐴𝐶𝐴𝐷 ) ∨ ( 𝐵𝐶𝐵𝐷 ) ) → { 𝐴 , 𝐵 } ≠ { 𝐶 , 𝐷 } ) )