Metamath Proof Explorer


Theorem eqvrelqseqdisj5

Description: Lemma for the Partition-Equivalence Theorem pet2 . (Contributed by Peter Mazsa, 15-Jul-2020) (Revised by Peter Mazsa, 22-Sep-2021)

Ref Expression
Assertion eqvrelqseqdisj5 ( ( EqvRel 𝑅 ∧ ( 𝐵 / 𝑅 ) = 𝐴 ) → Disj ( 𝑆 ⋉ ( ◡ E ↾ 𝐴 ) ) )

Proof

Step Hyp Ref Expression
1 eqvrelqseqdisj3 ⊢ ( ( EqvRel 𝑅 ∧ ( 𝐵 / 𝑅 ) = 𝐴 ) → Disj ( ◡ E ↾ 𝐴 ) )
2 disjimxrn ⊢ ( Disj ( ◡ E ↾ 𝐴 ) → Disj ( 𝑆 ⋉ ( ◡ E ↾ 𝐴 ) ) )
3 1 2 syl ⊢ ( ( EqvRel 𝑅 ∧ ( 𝐵 / 𝑅 ) = 𝐴 ) → Disj ( 𝑆 ⋉ ( ◡ E ↾ 𝐴 ) ) )