Metamath Proof Explorer


Theorem cnvimarndmOLD

Description: Obsolete version of cnvimarndm as of 29-Sep-2026. (Contributed by Jeff Hankins, 15-Jul-2009) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion cnvimarndmOLD ⊢ A -1 ran ⁡ A = dom ⁡ A

Proof

Step Hyp Ref Expression
1 imadmrn ⊢ A -1 dom ⁡ A -1 = ran ⁡ A -1
2 df-rn ⊢ ran ⁡ A = dom ⁡ A -1
3 2 imaeq2i ⊢ A -1 ran ⁡ A = A -1 dom ⁡ A -1
4 dfdm4 ⊢ dom ⁡ A = ran ⁡ A -1
5 1 3 4 3eqtr4i ⊢ A -1 ran ⁡ A = dom ⁡ A