Metamath Proof Explorer


Theorem cossssid

Description: Equivalent expressions for the class of cosets by R to be a subset of the identity class. (Contributed by Peter Mazsa, 27-Jul-2021)

Ref Expression
Assertion cossssid ⊢ ≀ R ⊆ I ↔ ≀ R ⊆ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R

Proof

Step Hyp Ref Expression
1 iss2 ⊢ ≀ R ⊆ I ↔ ≀ R = I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R
2 refrelcoss2 ⊢ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R ⊆ ≀ R ∧ Rel ⁡ ≀ R
3 2 simpli ⊢ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R ⊆ ≀ R
4 eqss ⊢ ≀ R = I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R ↔ ≀ R ⊆ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R ∧ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R ⊆ ≀ R
5 3 4 mpbiran2 ⊢ ≀ R = I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R ↔ ≀ R ⊆ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R
6 1 5 bitri ⊢ ≀ R ⊆ I ↔ ≀ R ⊆ I ∩ dom ⁡ ≀ R × ran ⁡ ≀ R