Metamath Proof Explorer


Theorem idresrnsscocnv2

Description: A class precomposed with its converse includes the identity relation restricted to its range. (Contributed by BJ, 25-Oct-2026)

Ref Expression
Assertion idresrnsscocnv2 ( I ↾ ran 𝐴 ) ⊆ ( 𝐴 ∘ ◡ 𝐴 )

Proof

Step Hyp Ref Expression
1 idresdmsscocnv1 ⊢ ( I ↾ dom ◡ 𝐴 ) ⊆ ( ◡ ◡ 𝐴 ∘ ◡ 𝐴 )
2 df-rn ⊢ ran 𝐴 = dom ◡ 𝐴
3 2 eqcomi ⊢ dom ◡ 𝐴 = ran 𝐴
4 3 reseq2i ⊢ ( I ↾ dom ◡ 𝐴 ) = ( I ↾ ran 𝐴 )
5 cocnvcnv1 ⊢ ( ◡ ◡ 𝐴 ∘ ◡ 𝐴 ) = ( 𝐴 ∘ ◡ 𝐴 )
6 1 4 5 3sstr3i ⊢ ( I ↾ ran 𝐴 ) ⊆ ( 𝐴 ∘ ◡ 𝐴 )