Metamath Proof Explorer


Theorem trcleq2lem

Description: Equality implies bijection. (Contributed by RP, 5-May-2020)

Ref Expression
Assertion trcleq2lem ⊢ A = B → R ⊆ A ∧ A ∘ A ⊆ A ↔ R ⊆ B ∧ B ∘ B ⊆ B

Proof

Step Hyp Ref Expression
1 sseq2 ⊢ A = B → R ⊆ A ↔ R ⊆ B
2 id ⊢ A = B → A = B
3 2 2 coeq12d ⊢ A = B → A ∘ A = B ∘ B
4 3 2 sseq12d ⊢ A = B → A ∘ A ⊆ A ↔ B ∘ B ⊆ B
5 1 4 anbi12d ⊢ A = B → R ⊆ A ∧ A ∘ A ⊆ A ↔ R ⊆ B ∧ B ∘ B ⊆ B