Theorem smodm 8352

Description: The domain of a strictly monotone function is an ordinal. (Contributed by Andrew Salmon, 16-Nov-2011.)

Assertion

Ref	Expression
smodm	⊢ (Smo 𝐴 → Ord dom 𝐴)

Proof of Theorem smodm

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-smo 8347	. 2 ⊢ (Smo 𝐴 ↔ (𝐴:dom 𝐴⟶On ∧ Ord dom 𝐴 ∧ ∀𝑥 ∈ dom 𝐴∀𝑦 ∈ dom 𝐴(𝑥 ∈ 𝑦 → (𝐴‘𝑥) ∈ (𝐴‘𝑦))))
2	1	simp2bi 1164	1 ⊢ (Smo 𝐴 → Ord dom 𝐴)

This proof depends on syntax axioms:   → wi 4   ∈ wcel 2145  ∀wral 3077  dom cdm 5651  Ord word 6360  Oncon0 6361  ⟶wf 6533  ‘cfv 6537  Smo wsmo 8346

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This proof depends on definitions:  df-bi 210  df-an 402  df-3an 1105  df-smo 8347

This theorem is used by:  smores2  8355  smodm2  8356  smoel  8361