Theorem cosselcnvrefrels2

Description: Necessary and sufficient condition for a coset relation to be an element of the converse reflexive relation class. (Contributed by Peter Mazsa, 25-Aug-2021)

	Ref	Expression
Assertion	cosselcnvrefrels2	⊢ ( ≀ 𝑅 ∈ CnvRefRels ↔ ( ≀ 𝑅 ⊆ I ∧ ≀ 𝑅 ∈ Rels ) )

Proof

Step	Hyp	Ref	Expression
1		elcnvrefrels2	⊢ ( ≀ 𝑅 ∈ CnvRefRels ↔ ( ≀ 𝑅 ⊆ ( I ∩ ( dom ≀ 𝑅 × ran ≀ 𝑅 ) ) ∧ ≀ 𝑅 ∈ Rels ) )
2		cossssid	⊢ ( ≀ 𝑅 ⊆ I ↔ ≀ 𝑅 ⊆ ( I ∩ ( dom ≀ 𝑅 × ran ≀ 𝑅 ) ) )
3	2	anbi1i	⊢ ( ( ≀ 𝑅 ⊆ I ∧ ≀ 𝑅 ∈ Rels ) ↔ ( ≀ 𝑅 ⊆ ( I ∩ ( dom ≀ 𝑅 × ran ≀ 𝑅 ) ) ∧ ≀ 𝑅 ∈ Rels ) )
4	1 3	bitr4i	⊢ ( ≀ 𝑅 ∈ CnvRefRels ↔ ( ≀ 𝑅 ⊆ I ∧ ≀ 𝑅 ∈ Rels ) )