Theorem f1odm 5505

Description: The domain of a one-to-one onto mapping. (Contributed by NM, 8-Mar-2014.)

Assertion

Ref	Expression
f1odm	⊢ (𝐹:𝐴–1-1-onto→𝐵 → dom 𝐹 = 𝐴)

Proof of Theorem f1odm

Step	Hyp	Ref	Expression
1		f1ofn 5502	. 2 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → 𝐹 Fn 𝐴)
2		fndm 5354	. 2 ⊢ (𝐹 Fn 𝐴 → dom 𝐹 = 𝐴)
3	1, 2	syl 14	1 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → dom 𝐹 = 𝐴)

Syntax hints:   → wi 4   = wceq 1364  dom cdm 4660   Fn wfn 5250  –1-1-onto→wf1o 5254

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107

This theorem depends on definitions:  df-bi 117  df-fn 5258  df-f 5259  df-f1 5260  df-f1o 5262

This theorem is referenced by:  f1imacnv  5518  f1opw2  6126  xpcomco  6882  mapen  6904  ssenen  6909  phplem4  6913  phplem4on  6925  dif1en  6937  fiintim  6987  caseinl  7152  caseinr  7153  ctssdccl  7172  fihasheqf1oi  10861  hashfacen  10910  fisumss  11538